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Sample records for syncytial virus replication

  1. Replication and clearance of respiratory syncytial virus - Apoptosis is an important pathway of virus clearance after experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Viuff, B.; Tjørnehøj, Kirsten; Larsen, Lars Erik

    2002-01-01

    and clearance in a natural target animal. Replication of BRSV was demonstrated in the luminal part of the respiratory epithelial cells and replication in the upper respiratory tract preceded the replication in the lower respiratory tract. Virus excreted to the lumen of the respiratory tract was cleared...... and the infections with human respiratory syncytial. virus and BRSV have similar clinical, pathological, and epidemiological characteristics. In this study we used experimental BRSV infection in calves as a model of respiratory syncytial virus infection to demonstrate important aspects of viral replication......Human respiratory syncytial virus is an important cause of severe respiratory disease in young children, the elderly, and in immunocompromised adults. Similarly, bovine respiratory syncytial virus (BRSV) is causing severe, sometimes fatal, respiratory disease in calves. Both viruses are pneumovirus...

  2. Respiratory Syncytial Virus

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Respiratory Syncytial Virus (RSV) Credit: CDC This is the ... the United States. Why Is the Study of Respiratory Syncytial Virus (RSV) a Priority for NIAID? In ...

  3. Respiratory syncytial virus (RSV)

    Science.gov (United States)

    RSV; Palivizumab; Respiratory syncytial virus immune globulin; Bronchiolitis - RSV ... Crowe JE. Respiratory syncytial virus. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ...

  4. Respiratory Syncytial Virus (RSV)

    Centers for Disease Control (CDC) Podcasts

    Respiratory Syncytial Virus, or RSV, causes cold-like symptoms but can be serious for infants and older adults. In this podcast, CDC’s Dr. Eileen Schneider discusses this common virus and offers tips to prevent its spread.

  5. Respiratory Syncytial Virus (RSV)

    Centers for Disease Control (CDC) Podcasts

    2013-02-04

    Respiratory Syncytial Virus, or RSV, causes cold-like symptoms but can be serious for infants and older adults. In this podcast, CDC’s Dr. Eileen Schneider discusses this common virus and offers tips to prevent its spread.  Created: 2/4/2013 by National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases (DVD).   Date Released: 2/13/2013.

  6. Respiratory Syncytial Virus Vaccines

    OpenAIRE

    Dudas, Robert A.; Karron, Ruth A.

    1998-01-01

    Respiratory syncytial virus (RSV) is the most important cause of viral lower respiratory tract illness (LRI) in infants and children worldwide and causes significant LRI in the elderly and in immunocompromised patients. The goal of RSV vaccination is to prevent serious RSV-associated LRI. There are several obstacles to the development of successful RSV vaccines, including the need to immunize very young infants, who may respond inadequately to vaccination; the existence of two antigenically d...

  7. 2'-5'-Oligoadenylate Synthetase-Like Protein Inhibits Respiratory Syncytial Virus Replication and Is Targeted by the Viral Nonstructural Protein 1.

    Science.gov (United States)

    Dhar, Jayeeta; Cuevas, Rolando A; Goswami, Ramansu; Zhu, Jianzhong; Sarkar, Saumendra N; Barik, Sailen

    2015-10-01

    2'-5'-Oligoadenylate synthetase-like protein (OASL) is an interferon-inducible antiviral protein. Here we describe differential inhibitory activities of human OASL and the two mouse OASL homologs against respiratory syncytial virus (RSV) replication. Interestingly, nonstructural protein 1 (NS1) of RSV promoted proteasome-dependent degradation of specific OASL isoforms. We conclude that OASL acts as a cellular antiviral protein and that RSV NS1 suppresses this function to evade cellular innate immunity and allow virus growth. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  8. A Respiratory Syncytial Virus Vaccine Vectored by a Stable Chimeric and Replication-Deficient Sendai Virus Protects Mice without Inducing Enhanced Disease.

    Science.gov (United States)

    Wiegand, Marian Alexander; Gori-Savellini, Gianni; Gandolfo, Claudia; Papa, Guido; Kaufmann, Christine; Felder, Eva; Ginori, Alessandro; Disanto, Maria Giulia; Spina, Donatella; Cusi, Maria Grazia

    2017-05-15

    Respiratory syncytial virus (RSV) is a major cause of severe respiratory infections in children and elderly people, and no marketed vaccine exists. In this study, we generated and analyzed a subunit vaccine against RSV based on a novel genome replication-deficient Sendai virus (SeV) vector. We inserted the RSV F protein, known to be a genetically stable antigen, into our vector in a specific way to optimize the vaccine features. By exchanging the ectodomain of the SeV F protein for its counterpart from RSV, we created a chimeric vectored vaccine that contains the RSV F protein as an essential structural component. In this way, the antigen is actively expressed on the surfaces of vaccine particles in its prefusion conformation, and as recently reported for other vectored vaccines, the occurrence of silencing mutations of the transgene in the vaccine genome can be prevented. In addition, its active gene expression contributes to further stimulation of the immune response. In order to understand the best route of immunization, we compared vaccine efficacies after intranasal (i.n.) or intramuscular (i.m.) immunization of BALB/c mice. Via both routes, substantial RSV-specific immune responses were induced, consisting of serum IgG and neutralizing antibodies, as well as cytotoxic T cells. Moreover, i.n. immunization was also able to stimulate specific mucosal IgA in the upper and lower respiratory tract. In virus challenge experiments, animals were protected against RSV infection after both i.n. and i.m. immunization without inducing vaccine-enhanced disease. Above all, the replication-deficient SeV appeared to be safe and well tolerated. IMPORTANCE Respiratory syncytial virus (RSV) is a major cause of respiratory diseases in young children and elderly people worldwide. There is a great demand for a licensed vaccine. Promising existing vaccine approaches based on live-attenuated vaccines or viral vectors have suffered from unforeseen drawbacks related to immunogenicity

  9. Learn about Respiratory Syncytial Virus (RSV)

    Science.gov (United States)

    ... the Planet and Lung Health by Reducing Air Pollution Blog: JUUL: A Wolf in Sheep's Clothing '; } else { ... while processing XML file."); } }); } } --> Blank Section Header Lung Disease Lookup RSV Learn About Respiratory Syncytial Virus (RSV) RSV Symptoms, Causes & Risk Factors ...

  10. Neonatal respiratory syncytial virus infection: role of transplacentally and breast milk-acquired antibodies.

    OpenAIRE

    Wong, D T; Ogra, P L

    1986-01-01

    The effect of transplacentally and breast milk-acquired antibodies on respiratory syncytial virus infection was studied in neonatal and 2-month-old cotton rats. Adult female rats infected intranasally with live virus regularly produced virus-specific antibodies in the serum, colostrum, and breast milk. By using foster feeding techniques, we showed that both transplacentally and breast milk-acquired antibodies were effective in reducing the replication of respiratory syncytial virus in the lun...

  11. Bovine respiratory syncytial virus (BRSV): A review

    DEFF Research Database (Denmark)

    Larsen, Lars Erik

    2000-01-01

    Bovine respiratory syncytial virus (BRSV) infection is the major cause of respiratory disease in calves during the first year of life. The study of the virus has been difficult because of its lability and very poor growth in cell culture. However, during the last decade, the introduction of new...... complex and unpredictable which makes the diagnosis and subsequent therapy very difficult. BRSV is closely related to human respiratory syncytial virus (HRSV) which is an important cause of respiratory disease in young children. In contrast to BRSV, the recent knowledge of HRSV is regularly extensively...

  12. Human Respiratory Syncytial Virus and Human Metapneumovirus

    OpenAIRE

    Luciana Helena Antoniassi da Silva; Fernando Rosado Spilki; Adriana Gut Lopes Riccetto; Emilio Elias Baracat; Clarice Weis Arns

    2009-01-01

    The human respiratory syncytial virus (hRSV) and the human metapneumovírus (hMPV) are main etiological agents of acute respiratory infections (ARI). The ARI is an important cause of childhood morbidity and mortality worldwide.  hRSV and hMPV are members of the Paramyxoviridae. They are enveloped, non-segmented viruses, with negative-sense single stranded genomes. Respiratory syncytial virus (hRSV) is the best characterized agent viral of this group, associated with respiratory diseases in...

  13. Respiratory syncytial virus neutralizing antibodies in cord blood, respiratory syncytial virus hospitalization, and recurrent wheeze

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Ravn, Henrik; Kristensen, Kim

    2008-01-01

    BACKGROUND: Respiratory syncytial virus (RSV) hospitalization is associated with wheeze. OBJECTIVE: To examine the influence of maternally derived RSV neutralizing antibodies in cord blood on RSV hospitalization and recurrent wheeze in infancy. METHODS: Among children from the Danish National Birth...

  14. BIOLOGY OF HUMAN RESPIRATORY SYNCYTIAL VIRUS: A ...

    African Journals Online (AJOL)

    DR. AMINU

    membrane of the eyes, mouth, or nose and possibly through the ... transmembrane anchor near the C terminus. It is cleaved into two ... immunity induced by previous strains (Hall, 2001). Fluctuations in the .... isolation, and other serological techniques. Antigen .... Respiratory syncytial virus in B.N. fields, D.M. Knipe and.

  15. Human Respiratory Syncytial Virus and Human Metapneumovirus

    Directory of Open Access Journals (Sweden)

    Luciana Helena Antoniassi da Silva

    2009-08-01

    Full Text Available The human respiratory syncytial virus (hRSV and the human metapneumovírus (hMPV are main etiological agents of acute respiratory infections (ARI. The ARI is an important cause of childhood morbidity and mortality worldwide.  hRSV and hMPV are members of the Paramyxoviridae. They are enveloped, non-segmented viruses, with negative-sense single stranded genomes. Respiratory syncytial virus (hRSV is the best characterized agent viral of this group, associated with respiratory diseases in lower respiratory tract. Recently, a new human pathogen belonging to the subfamily Pneumovirinae was identified, the human metapneumovirus (hMPV, which is structurally similar to the hRSV, in genomic organization, viral structure, antigenicity and clinical symptoms.  The subfamily Pneumovirinae contains two genera: genus Pneumovirus contains hRSV, the bovine (bRSV, as well as the ovine and caprine respiratory syncytial virus and pneumonia virus of mice, the second genus Metapneumovirus, consists of avian metapneumovirus (aMPV and human metapneumovirus (hMPV. In this work, we present a brief narrative review of the literature on important aspects of the biology, epidemiology and clinical manifestations of infections by two respiratory viruses.

  16. 21 CFR 866.3480 - Respiratory syncytial virus serological reagents.

    Science.gov (United States)

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3480... respiratory syncytial viruses from clinical specimens or from tissue culture isolates derived from clinical...

  17. Hilar enlargement in respiratory syncytial virus pneumonia

    International Nuclear Information System (INIS)

    Odita, J.C.; Aghahowa, J.E.; Nwankwo, M.

    1989-01-01

    The clinical and radiographic features of ten children with hilar enlargement in association with proven Respiratory Syncytial Virus (RSV) infection are described. Hilar enlargement was seen in 10/35 children with RSV infection, and was invariably unilateral and right sided. It is recommended that RSV pneumonia be considered in children with unilateral hilar enlargement if tuberculosis has been excluded, and the onset of disease is rapid. (orig.)

  18. Biology of human respiratory syncytial virus: a review | Aliyu | Bayero ...

    African Journals Online (AJOL)

    Acute lower respiratory tract infection is one of the major causes of mortality and morbidity in young children worldwide. Respiratory syncytial virus (RSV) is the single most important viral cause of lower respiratory tract infection during infancy and early childhood worldwide. Respiratory syncytial virus belongs to the ...

  19. Simultaneous detection of respiratory syncytial virus types A and B ...

    African Journals Online (AJOL)

    Tharwat Ezzat Deraz

    2012-02-28

    Feb 28, 2012 ... Abstract Background: Respiratory syncytial virus (RSV) types A and B and influenza A and B cause about .... plied Science, Mannheim, Germany; Cat. ..... detection of human rhinoviruses, paramyxoviruses, corona viruses, and ...

  20. A prime-boost vaccination strategy using attenuated Salmonella typhimurium and a replication-deficient recombinant adenovirus vector elicits protective immunity against human respiratory syncytial virus.

    Science.gov (United States)

    Fu, Yuan-Hui; He, Jin-Sheng; Wang, Xiao-Bo; Zheng, Xian-Xian; Wu, Qiang; Xie, Can; Zhang, Mei; Wei, Wei; Tang, Qian; Song, Jing-Dong; Qu, Jian-Guo; Hong, Tao

    2010-04-23

    Human respiratory syncytial virus (RSV), for which no clinically approved vaccine is available yet, is globally a serious pediatric pathogen of the lower respiratory tract. Several approaches have been used to develop vaccines against RSV, but none of these have been approved for use in humans. An efficient vaccine-enhancing strategy for RSV is still urgently needed. We found previously that oral SL7207/pcDNA3.1/F and intranasal FGAd/F were able to induce an effective protective immune response against RSV. The heterologous prime-boost immunization regime has been reported recently to be an efficient vaccine-enhancing strategy. Therefore, we investigated the ability of an oral SL7207/pcDNA3.1/F prime and intranasal (i.n.) FGAd/F boost regimen to generate immune responses to RSV. The SL7207/pcDNA3.1/F prime-FGAd/F boost regimen generated stronger RSV-specific humoral and mucosal immune responses in BALB/c mice than the oral SL7207/pcDNA3.1/F regimen alone, and stronger specific cellular immune responses than the i.n. FGAd/F regimen alone. Histopathological analysis showed an increased efficacy against RSV challenge by the heterologous prime-boost regimen. These results suggest that such a heterologous prime-boost strategy can enhance the efficacy of either the SL7207 or the FGAd vector regimen in generating immune responses in BALB/c mice. 2010 Elsevier Inc. All rights reserved.

  1. Gold nanorod vaccine for respiratory syncytial virus

    International Nuclear Information System (INIS)

    Stone, John W; Thornburg, Natalie J; Blum, David L; Kuhn, Sam J; Crowe Jr, James E; Wright, David W

    2013-01-01

    Respiratory syncytial virus (RSV) is a major cause of pneumonia and wheezing in infants and the elderly, but to date there is no licensed vaccine. We developed a gold nanorod construct that displayed the major protective antigen of the virus, the fusion protein (F). Nanorods conjugated to RSV F were formulated as a candidate vaccine preparation by covalent attachment of viral protein using a layer-by-layer approach. In vitro studies using ELISA, electron microscopy and circular dichroism revealed that conformation-dependent epitopes were maintained during conjugation, and transmission electron microscopy studies showed that a dispersed population of particles could be achieved. Human dendritic cells treated with the vaccine induced immune responses in primary human T cells. These results suggest that this vaccine approach may be a potent method for immunizing against viruses such as RSV with surface glycoproteins that are targets for the human immune response. (paper)

  2. Respiratory Syncytial Virus Infection (RSV): Transmission and Prevention

    Science.gov (United States)

    ... of Search Controls Search Form Controls Cancel Submit Respiratory Syncytial Virus Infection (RSV) Note: Javascript is disabled ... 2018 Content source: National Center for Immunization and Respiratory Diseases (NCIRD) , Division of Viral Diseases Email Recommend ...

  3. Respiratory Syncytial Virus (RSV) Test: MedlinePlus Lab Test Information

    Science.gov (United States)

    ... this page: https://medlineplus.gov/labtests/respiratorysyncytialvirusrsvtest.html Respiratory Syncytial Virus (RSV) Test To use the sharing ... is an RSV test? RSV , which stands for respiratory syncytial virus, is an infection that affects the ...

  4. Respiratory Syncytial Virus Bronchiolitis in Children.

    Science.gov (United States)

    Smith, Dustin K; Seales, Sajeewane; Budzik, Carol

    2017-01-15

    Bronchiolitis is a common lower respiratory tract infection in infants and young children, and respiratory syncytial virus (RSV) is the most common cause of this infection. RSV is transmitted through contact with respiratory droplets either directly from an infected person or self-inoculation by contaminated secretions on surfaces. Patients with RSV bronchiolitis usually present with two to four days of upper respiratory tract symptoms such as fever, rhinorrhea, and congestion, followed by lower respiratory tract symptoms such as increasing cough, wheezing, and increased respiratory effort. In 2014, the American Academy of Pediatrics updated its clinical practice guideline for diagnosis and management of RSV bronchiolitis to minimize unnecessary diagnostic testing and interventions. Bronchiolitis remains a clinical diagnosis, and diagnostic testing is not routinely recommended. Treatment of RSV infection is mainly supportive, and modalities such as bronchodilators, epinephrine, corticosteroids, hypertonic saline, and antibiotics are generally not useful. Evidence supports using supplemental oxygen to maintain adequate oxygen saturation; however, continuous pulse oximetry is no longer required. The other mainstay of therapy is intravenous or nasogastric administration of fluids for infants who cannot maintain their hydration status with oral fluid intake. Educating parents on reducing the risk of infection is one of the most important things a physician can do to help prevent RSV infection, especially early in life. Children at risk of severe lower respiratory tract infection should receive immunoprophylaxis with palivizumab, a humanized monoclonal antibody, in up to five monthly doses. Prophylaxis guidelines are restricted to infants born before 29 weeks' gestation, infants with chronic lung disease of prematurity, and infants and children with hemodynamically significant heart disease.

  5. Strategies for preventing respiratory syncytial virus.

    Science.gov (United States)

    Forbes, Michael

    2008-12-01

    Prevention of respiratory syncytial virus (RSV) infection-crucial for decreasing the burden associated with this disease-is discussed. Predictable outbreaks of RSV occur annually throughout the U.S. During these outbreaks, RSV infection spreads readily among children through close contact with infected individuals or contact with contaminated surfaces or objects. RSV is the leading cause of infant hospitalization and is associated with life-changing and life-threatening complications. Prevention is important for reducing the associated morbidity and mortality. The American Academy of Pediatrics (AAP) has outlined ways to prevent RSV transmission. According to the AAP, frequent hand washing is the most important strategy for reducing the burden of RSV disease. Other methods for controlling nosocomial spread of RSV include the use of gloves, frequent glove changes, and isolating or cohorting patients. General prevention measures that can be undertaken by family members include smoking cessation, breastfeeding, and avoiding situations, whenever possible, where exposure to RSV cannot be controlled. Passive immunoprophylaxis with palivizumab, the only agent approved by the FDA, reduces hospitalization in high-risk children. Palivizumab is currently the only agent approved by the FDA for the prevention of RSV infections in high-risk children. Not every child is equally at risk for serious RSV disease, and immunoprophylaxis is indicated only for certain high-risk children. The AAP has issued specific guidelines for RSV immunoprophylaxis with palivizumab. Other therapies are emerging for the prevention of RSV, including a new, enhanced-potency, humanized RSV monoclonal antibody and several different types of vaccines. RSV causes an annual, predictable epidemic. Treatment remains exclusively supportive. Prevention remains the cornerstone of disease management. The AAP has issued guidelines to protect those at high risk.

  6. Invasive pneumococcal and meningococcal disease : association with influenza virus and respiratory syncytial virus activity?

    NARCIS (Netherlands)

    Jansen, A G S C; Sanders, E A M; VAN DER Ende, A; VAN Loon, A M; Hoes, A W; Hak, E

    2008-01-01

    Few studies have examined the relationship between viral activity and bacterial invasive disease, considering both influenza virus and respiratory syncytial virus (RSV). This study aimed to assess the potential relationship between invasive pneumococcal disease (IPD), meningococcal disease (MD), and

  7. A recombinant anchorless respiratory syncytial virus (RSV) fusion (F) protein/monophosphoryl lipid A (MPL) vaccine protects against RSV-induced replication and lung pathology.

    Science.gov (United States)

    Blanco, Jorge C G; Boukhvalova, Marina S; Pletneva, Lioubov M; Shirey, Kari Ann; Vogel, Stefanie N

    2014-03-14

    We previously demonstrated that the severe cytokine storm and pathology associated with RSV infection following intramuscular vaccination of cotton rats with FI-RSV Lot 100 could be completely abolished by formulating the vaccine with the mild TLR4 agonist and adjuvant, monophosphoryl lipid A (MPL). Despite this significant improvement, the vaccine failed to blunt viral replication in the lungs. Since MPL is a weak TLR4 agonist, we hypothesized that its adjuvant activity was mediated by modulating the innate immune response of respiratory tract resident macrophages. Therefore, we developed a new vaccine preparation with purified, baculovirus expressed, partially purified, anchorless RSV F protein formulated with synthetic MPL that was administered to cotton rats intranasally, followed by an intradermal boost. This novel formulation and heterologous "prime/boost" route of administration resulted in decreased viral titers compared to that seen in animals vaccinated with F protein alone. Furthermore, animals vaccinated by this route showed no evidence of enhanced lung pathology upon RSV infection. This indicates that MPL acts as an immune modulator that protects the host from vaccine-enhanced pathology, and reduces RSV replication in the lower respiratory tract when administered by a heterologous prime/boost immunization regimen. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Seasonal variation of maternally derived respiratory syncytial virus antibodies and association with infant hospitalizations for respiratory syncytial virus

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Ravn, Henrik; Kristensen, Kim

    2009-01-01

    This study used 459 prospectively sampled cord blood samples to examine the association between maternally derived respiratory syncytial virus (RSV)-neutralizing antibodies and the RSV hospitalization season in Denmark. We found a clear temporal association and suggest that RSV-neutralizing antib......This study used 459 prospectively sampled cord blood samples to examine the association between maternally derived respiratory syncytial virus (RSV)-neutralizing antibodies and the RSV hospitalization season in Denmark. We found a clear temporal association and suggest that RSV......-neutralizing antibody level plays a role in the RSV seasonal pattern....

  9. Animal models of human respiratory syncytial virus disease

    NARCIS (Netherlands)

    Bem, Reinout A.; Domachowske, Joseph B.; Rosenberg, Helene F.

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for

  10. Peroxisome proliferator-activated receptor-γ agonists inhibit the replication of respiratory syncytial virus (RSV) in human lung epithelial cells

    International Nuclear Information System (INIS)

    Arnold, Ralf; Koenig, Wolfgang

    2006-01-01

    We have previously shown that peroxisome proliferator-activated receptor-γ (PPARγ) agonists inhibited the inflammatory response of RSV-infected human lung epithelial cells. In this study, we supply evidence that specific PPARγ agonists (15d-PGJ 2 , ciglitazone, troglitazone, Fmoc-Leu) efficiently blocked the RSV-induced cytotoxicity and development of syncytia in tissue culture (A549, HEp-2). All PPARγ agonists under study markedly inhibited the cell surface expression of the viral G and F protein on RSV-infected A549 cells. This was paralleled by a reduced cellular amount of N protein-encoding mRNA determined by real-time RT-PCR. Concomitantly, a reduced release of infectious progeny virus into the cell supernatants of human lung epithelial cells (A549, normal human bronchial epithelial cells (NHBE)) was observed. Similar results were obtained regardless whether PPARγ agonists were added prior to RSV infection or thereafter, suggesting that the agonists inhibited viral gene expression and not the primary adhesion or fusion process

  11. Increased concordance of severe respiratory syncytial virus infection in identical twins

    DEFF Research Database (Denmark)

    Thomsen, Simon Francis; Stensballe, Lone Graff; Skytthe, Axel

    2008-01-01

    (concordance rate: 0.66 vs 0.53), which suggests genetic influences on disease severity. Genetic factors accounted for 16%, family environment for 73%, and nonshared environment for 11% of the individual susceptibility to develop severe respiratory syncytial virus infection. CONCLUSIONS: The severity...... of respiratory syncytial virus infection is determined partly by genetic factors. This result should stimulate the search for genetic markers of disease severity.......OBJECTIVE: We estimated differences in the severity of respiratory syncytial virus infection attributable to genetic and environmental factors. METHODS: Record linkage data on hospitalizations attributable to respiratory syncytial virus infection were gathered on all twins (12,346 pairs) born...

  12. Management of the infant with respiratory syncytial virus.

    Science.gov (United States)

    Corey, M A; Clore, E R

    1991-04-01

    This article examines updated clinical information concerning respiratory syncytial virus (RSV) infection including epidemiology, pathology, clinical manifestations, diagnosis, treatment, nosocomial infection, and prognosis. Also presented is current information on ribavirin therapy, its side effects, and precautions. Research related to the most effective isolation methodology is discussed, as well as nursing diagnoses based on Gordon's Functional Health Patterns and interventions for the infant hospitalized with RSV bronchiolitis and/or pneumonia.

  13. Respiratory syncytial virus mechanisms to interfere with type 1 interferons.

    Science.gov (United States)

    Barik, Sailen

    2013-01-01

    Respiratory syncytial virus (RSV) is a member of the Paramyxoviridae family that consists of viruses with nonsegmented negative-strand RNA genome. Infection by these viruses triggers the innate antiviral response of the host, mainly type I interferon (IFN). Essentially all other viruses of this family produce IFN suppressor functions by co-transcriptional RNA editing. In contrast, RSV has evolved two unique nonstructural proteins, NS1 and NS2, to effectively serve this purpose. Together, NS1 and NS2 degrade or sequester multiple signaling proteins that affect both IFN induction and IFN effector functions. While the mechanism of action of NS1 and NS2 is a subject of active research, their effect on adaptive immunity is also being recognized. In this review, we discuss various aspects of NS1 and NS2 function with implications for vaccine design.

  14. Interference Between Respiratory Syncytial Virus and Human Rhinovirus Infection in Infancy

    NARCIS (Netherlands)

    Achten, Niek B.; Wu, Pingsheng; Bont, Louis; Blanken, Maarten O; Gebretsadik, Tebeb; Chappell, James D; Wang, Li; Yu, Chang; Larkin, Emma K; Carroll, Kecia N; Anderson, Larry J; Moore, Martin L; Sloan, Chantel D; Hartert, Tina V

    2017-01-01

    Background.: Respiratory syncytial virus (RSV) and human rhinovirus (HRV) are the most common viruses associated with acute respiratory tract infections in infancy. Viral interference is important in understanding respiratory viral circulation and the impact of vaccines. Methods.: To study viral

  15. Risk factors for admission and the role of respiratory syncytial virus ...

    African Journals Online (AJOL)

    disease and poor outcomes when exposed to the influenza virus. Studies of CTL responses ... (IL)8 and IL2) and human neutrophil elastase play a significant ~ role in the ..... Prophylaxis against respiratory syncytial virus in premature infants.

  16. Respiratory syncytial virus, pneumonia virus of mice, and influenza A virus differently affect respiratory allergy in mice

    NARCIS (Netherlands)

    Barends, M.; de Rond, L. G. H.; Dormans, J.; van Oosten, M.; Boelen, A.; Neijens, H. J.; Osterhaus, A. D. M. E.; Kimman, T. G.

    2004-01-01

    Respiratory viral infections in early childhood may interact with the immune system and modify allergen sensitization and/or allergic manifestations. In mice, respiratory syncytial virus (RSV) infection during allergic provocation aggravates the allergic T helper (Th) 2 immune response,

  17. A randomized trial of montelukast in respiratory syncytial virus postbronchiolitis

    DEFF Research Database (Denmark)

    Bisgaard, Hans

    2003-01-01

    Infants often develop reactive airway disease after respiratory syncytial virus (RSV) bronchiolitis. Cysteinyl-leukotrienes (cys-LT) are released during RSV infection and may contribute to the inflammation. We hypothesized that a cys-LT receptor antagonist would ameliorate reactive airway disease...... subsequent to RSV bronchiolitis. One hundred and thirty infants who were 3 to 36 months old, hospitalized with acute RSV bronchiolitis, were randomized into a double-blind, parallel comparison of 5-mg montelukast chewable tablets or matching placebo given for 28 days starting within 7 days of symptom debut...

  18. Need for a safe vaccine against respiratory syncytial virus infection

    Directory of Open Access Journals (Sweden)

    Joo-Young Kim

    2012-09-01

    Full Text Available Human respiratory syncytial virus (HRSV is a major cause of severe respiratory tract illnesses in infants and young children worldwide. Despite its importance as a respiratory pathogen, there is currently no licensed vaccine for HRSV. Following failure of the initial trial of formalin-inactivated virus particle vaccine, continuous efforts have been made for the development of safe and efficacious vaccines against HRSV. However, several obstacles persist that delay the development of HRSV vaccine, such as the immature immune system of newborn infants and the possible Th2-biased immune responses leading to subsequent vaccine-enhanced diseases. Many HRSV vaccine strategies are currently being developed and evaluated, including live-attenuated viruses, subunit-based, and vector-based candidates. In this review, the current HRSV vaccines are overviewed and the safety issues regarding asthma and vaccine-induced pathology are discussed.

  19. Study of montelukast for the treatment of respiratory symptoms of post-respiratory syncytial virus bronchiolitis in children

    DEFF Research Database (Denmark)

    Bisgaard, H.; Flores-Nunez, A.; Goh, A.

    2008-01-01

    RATIONALE: A pilot study (Bisgaard H; Study Group on Montelukast and Respiratory Syncytial Virus. A randomized trial of montelukast in respiratory syncytial virus postbronchiolitis. Am J Respir Crit Care Med 2003;167:379-383) reported the efficacy of montelukast in post-respiratory syncytial viru...

  20. Bovine respiratory syncytial virus ISCOMs - protection in the presence of maternal antibodies

    DEFF Research Database (Denmark)

    Hägglund, Sara; Hu, Ke-Fei; Larsen, Lars Erik

    2004-01-01

    The protection induced by immunostimulating complexes (ISCOMs) against bovine respiratory syncytial virus (BRSV) was evaluated and compared to that of a commercial inactivated vaccine (CV) in calves with BRSV-specific maternal antibodies. Following experimental challenge, controls (n = 4...

  1. Variation of respiratory syncytial virus and the relation with meteorological factors in different winter seasons.

    NARCIS (Netherlands)

    Meerhoff, T.J.; Paget, W.J.; Kimpen, J.L.; Schellevis, F.

    2009-01-01

    Background: Respiratory syncytial virus (RSV) is the most important viral agent causing severe respiratory disease in infants and children. In temperate climates, RSV activity typically peaks during winter. We have described the seasonal variation in RSV activity and investigated which

  2. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool

    Directory of Open Access Journals (Sweden)

    Flávio da Silva Mesquita

    2017-05-01

    Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

  3. Streptococcus pneumoniae enhances human respiratory syncytial virus infection in vitro and in vivo

    NARCIS (Netherlands)

    D.T. Nguyen (Tien); R.P.L. Louwen (Rogier); Elberse, K. (Karin); G. van Amerongen (Geert); S. Yüksel (Selma); A. Luijendijk (Ad); A.D.M.E. Osterhaus (Albert); W.P. Duprex (William Paul); R.L. de Swart (Rik)

    2015-01-01

    textabstractHuman respiratory syncytial virus (HRSV) and Streptococcus pneumoniae are important causative agents of respiratory tract infections. Both pathogens are associated with seasonal disease outbreaks in the pediatric population, and can often be detected simultaneously in infants

  4. Transmission of human respiratory syncytial virus in the immunocompromised ferret model

    NARCIS (Netherlands)

    de Waal, L. (Leon); S.L. Smits (Saskia); E.J.B. Veldhuis Kroeze (Edwin); G. van Amerongen (Geert); Pohl, M.O. (Marie O.); Osterhaus, A.D.M.E. (Albert D. M. E.); K.J. Stittelaar (Koert)

    2018-01-01

    textabstractHuman respiratory syncytial virus (HRSV) causes substantial morbidity and mortality in vulnerable patients, such as the very young, the elderly, and immunocompromised individuals of any age. Nosocomial transmission of HRSV remains a serious challenge in hospital settings, with

  5. Bovine respiratory syncytial virus: first serological evidence in Uruguay.

    Science.gov (United States)

    Costa, M; García, L; Yunus, A S; Rockemann, D D; Samal, S K; Cristina, J

    2000-01-01

    Bovine respiratory syncytial virus (BRSV) is a major cause of respiratory disease in calves resulting in a substantial economic loss for the cattle industry worldwide. In order to determine the presence of BRSV in Uruguay, an immunoenzymatic test was set up, using a recombinant BRSV nucleocapsid (N) protein as the antigen. The N protein was produced in Sf9 insect cells by a recombinant baculovirus expressing the N protein. Serum samples collected from one hundred cattle from four different geographic regions of Uruguay were analyzed. Antibodies against the N protein of BRSV were detected in 95% of the serum samples analyzed. These results show for the first time the presence of BRSV antibodies and suggest a widespread BRSV infection in the cattle population of Uruguay.

  6. Overview of respiratory syncytial virus disease in young children

    Directory of Open Access Journals (Sweden)

    Hoopes JM

    2012-07-01

    Full Text Available J Michael Hoopes1, Veena R Kumar21Medical Information, 2Medical and Scientific Affairs, MedImmune, LLC, Gaithersburg, MD, USAAbstract: Respiratory tract illnesses associated with respiratory syncytial virus (RSV were first reported more than 160 years ago and gained acceptance as a major respiratory pathogen in the late 1950s. Annual epidemics show a seasonal pattern typically beginning in the late fall and ending in early spring, averaging 5 months in length, and varying in time of onset, offset, and duration depending on geographic location. Manifestations of RSV illness primarily involve the upper respiratory tract but can spread to the lower airways and lead to bronchiolitis and/or pneumonia. Initial infection occurs in approximately two-thirds of children during the first year of life; nearly all children are infected at least once by 2 years of age. Reinfection is common throughout life, but initial illness during infancy generally presents with the most severe symptoms. Medical risk conditions that consistently predispose young children to serious lower respiratory tract infection (LRTI include congenital heart disease, chronic lung disease, and premature birth. Serious LRTI due to RSV is the leading cause of hospitalization in infants and young children worldwide and annual mean hospital expenses have been estimated to exceed 1 billion dollars in the United States. Young children incur more inpatient and outpatient visits for RSV LRTI than for influenza. RSV has a greater impact than influenza on hospitalization in infants with respect to length of stay, severity/course of disease, and resultant needs for ancillary treatments. Unlike many other childhood illnesses, a vaccine is not currently available for preventing RSV disease.Keywords: bronchopulmonary dysplasia, infants, hospitalization, prematurity, respiratory syncytial virus

  7. A Two-Dimensional Human Minilung System (Model for Respiratory Syncytial Virus Infections

    Directory of Open Access Journals (Sweden)

    Esmeralda Magro-Lopez

    2017-12-01

    Full Text Available Human respiratory syncytial virus (HRSV is a major cause of serious pediatric respiratory diseases that lacks effective vaccine or specific therapeutics. Although our understanding about HRSV biology has dramatically increased during the last decades, the need for adequate models of HRSV infection is compelling. We have generated a two-dimensional minilung from human embryonic stem cells (hESCs. The differentiation protocol yielded at least six types of lung and airway cells, although it is biased toward the generation of distal cells. We show evidence of HRSV replication in lung cells, and the induction of innate and proinflammatory responses, thus supporting its use as a model for the study of HRSV–host interactions.

  8. Identification of syncytial mutations in a clinical isolate of herpes simplex virus 2

    International Nuclear Information System (INIS)

    Muggeridge, Martin I.; Grantham, Michael L.; Johnson, F. Brent

    2004-01-01

    Small polykaryocytes resulting from cell fusion are found in herpes simplex virus (HSV) lesions in patients, but their significance for viral spread and pathogenesis is unclear. Although syncytial variants causing extensive fusion in tissue culture can be readily isolated from laboratory strains, they are rarely found in clinical isolates, suggesting that extensive cell fusion may be deleterious in vivo. Syncytial mutations have previously been identified for several laboratory strains, but not for clinical isolates of HSV type 2. To address this deficiency, we studied a recent syncytial clinical isolate, finding it to be a mixture of two syncytial and one nonsyncytial strain. The two syncytial strains have novel mutations in glycoprotein B, and in vitro cell fusion assays confirmed that they are responsible for syncytium formation. This panel of clinical strains may be ideal for examining the effect of increased cell fusion on pathogenesis

  9. Nosocomial infections by respiratory syncytial virus in children

    Directory of Open Access Journals (Sweden)

    Maren Karina Machado Echeverría

    2017-01-01

    Full Text Available Introduction: Acute lower respiratory infections cause high morbidity and mortality in children. Respiratory syncytial virus (RSV is the most prevalent agent. Some viruses cause serious nosocomial infections. In Uruguay, there is no knowledge about the morbidity and mortality of nosocomial infections by RSV. Objective: To determine the prevalence and characteristics of RSV nosocomial infections. Methodology: A descriptive study of acute lower respiratory infections caused by RSV in patients younger than two years, between 1/1/2005 and 31/12/2008 at the Hospital Pediátrico del Centro Hospitalario Pereira Rossell, was made. Results: Were identified 59 patients who represented an annual rate lower than 2/1000 discharges. The monthly distribution of cases was similar to the respiratory infections. No outbreaks were reported. The age of the patients had an average of 8.9 months, 39 were younger than one year, 23 had one or more risk factors for severe disease. Six patients required admission to intensive care unit, all required invasive ventilation, 3 died, none had chronic respiratory failure following the RSV nosocomial infection. Conclusions: During the study period, the RSV nosocomial infections showed a low prevalence, despite it highly contagiousness. They mainly affected young children, carriers of risk factors for severe ALRI. Their evolution was similar to that reported for RSV respiratory infections community acquired. It is important to maintain standards for the control of nosocomial infections, to prevent nosocomial transmission of RSV and prevent the onset of severe disease in hospitalized patients.

  10. The biennial cycle of respiratory syncytial virus outbreaks in Croatia

    Directory of Open Access Journals (Sweden)

    Drazenovic Vladimir

    2008-01-01

    Full Text Available Abstract The paper analyses the epidemic pattern of respiratory syncytial virus (RSV outbreaks in children in Croatia. Over a period of 11 consecutive winter seasons (1994–2005 3,435 inpatients from Zagreb County aged from infancy to 10 years who were hospitalised with acute respiratory tract infections were tested for RSV-infection. RSV was identified in nasopharyngeal secretions of patients by virus isolation in cell culture and by detection of viral antigen with monoclonal antibodies. In the Zagreb area, RSV outbreaks were proven to vary in a two-year cycle, which was repeated every 23–25 months. This biennial cycle comprised one larger and one smaller season. Climate factors correlated significantly with the number of RSV cases identified only in the large seasons, which suggests that the biennial cycle is likely to continue regardless of meteorological conditions. Knowledge of this biennial pattern should be useful in predicting the onset of RSV outbreaks in Croatia, and would facilitate planning for the prevention and control of RSV infections in the region.

  11. Burden of Severe Respiratory Syncytial Virus Disease Among 33-35 Weeks' Gestational Age Infants Born During Multiple Respiratory Syncytial Virus Seasons.

    LENUS (Irish Health Repository)

    Anderson, Evan J

    2017-02-01

    Moderate-late preterm infants, 33-35 weeks\\' gestational age (wGA), are at increased risk for respiratory syncytial virus hospitalization (RSVH). The objective of this study is to quantify the burden of RSVH in moderate-late preterm infants.

  12. Respiratory syncytial virus (RSV) pneumonia in a southern muriqui (Brachyteles arachnoides).

    Science.gov (United States)

    Santos, S V; Strefezzi, R F; Pissinatti, A; Takakura, C F H; Kanamura, C; Duarte, M I S; Catão-Dias, J L

    2012-12-01

    An adult male Brachyteles arachanoides, kept in captivity since 1990, was found dead without apparent clinical evidence. Necropsy report, histopathology, immunohistochemistry, and ultrastructural examination were conducted. Pulmonary syncytial cells were positive for respiratory syncytial virus (RSV), and ultrastructural examination revealed viral particles inside macrophages compatible with the Paramyxoviridae family. Muriquis are susceptible to RSV pneumonia followed by respiratory distress syndrome and death. © 2012 John Wiley & Sons A/S.

  13. Effect of human milk prostaglandins and lactoferrin on respiratory syncytial virus and rotavirus.

    Science.gov (United States)

    Grover, M; Giouzeppos, O; Schnagl, R D; May, J T

    1997-03-01

    The effect of lactoferrin and prostaglandins E and F2 alpha on the growth of rotavirus and respiratory syncytial virus in cell culture was investigated. Lactoferrin inhibited the growth of respiratory syncytial virus at a concentration tenfold lower than that normally present in human milk. The prostaglandins had no effect on either virus growth, even at a concentration of 100-fold more than that found in human milk. Lactoferrin may have some antiviral properties in human milk in addition to its known antibacterial functions.

  14. Burden of Respiratory Syncytial Virus Hospitalizations in Canada

    Directory of Open Access Journals (Sweden)

    Ian Mitchell

    2017-01-01

    Full Text Available Objective. To examine the socioeconomic burden of respiratory syncytial virus (RSV disease for Canadian infants hospitalized for the condition. Data and Methods. The descriptive study used data collected in Alberta, Canada, during 2 consecutive RSV seasons. Infants (<1 year of age were included if they had not received palivizumab and were hospitalized with a confirmed diagnosis of RSV. Hospitalization resource use and parental time burden, out-of-pocket costs, lost work productivity, and stress and anxiety were assessed. Results. 13.4% of all infants (n = 67 had intensive care unit (ICU admission, and average ICU stay for these infants was 6.5 days. Families had average out-of-pocket expenses of 736.69 Canadian dollars (CAD $, and the average time both parents spent in hospital was nearly 7 days (164.0 hours. For working parents (n = 43, average absenteeism was 49% and overall work impairment was 77.8%. Parents also exhibited significant parental stress (3.6 on the Parental Stressor Scale: 43.9 state anxiety and 36.9 trait anxiety scores. Conclusions. Results indicate a high burden associated with the hospitalization of an infant due to RSV disease in terms of resource use, time, productivity, costs, and stress, even among a population of infants not considered to be at risk for the condition.

  15. Autonomic dysfunction with early respiratory syncytial virus-related infection.

    Science.gov (United States)

    Stock, Claire; Teyssier, Georges; Pichot, Vincent; Goffaux, Philippe; Barthelemy, Jean-Claude; Patural, Hugues

    2010-08-25

    Apparent life-threatening events (ALTE) and/or prolonged apnoea have been well-documented during respiratory syncytial virus (RSV) infection in infants less than 2 months of age but fundamental mechanisms remain unclear. The possibility of a central origin for the development of severe cardiac and respiratory events encouraged us, to explore the autonomic nervous system (ANS) profile of infected infants, since ANS activity may contribute to the constellation of symptoms observed during severe forms of RSV bronchiolitis. Eight infants (2 preterm and 6 full-term) less than 2 months of age and presenting with severe and apnoeic forms of RSV infection were evaluated using non-invasive electrophysiological monitoring obtained simultaneously for approximately 2 consecutive hours, including a quiet sleep period. Eight control subjects, paired for gestational and postnatal age, were also evaluated. ANS status was monitored using electrocardiogram recordings and quantified through a frequency-domain analysis of heart rate variability (HRV). This included sympathetic (VLF and LF) and parasympathetic (HF) indices as well as a measure of baroreflex sensitivity (BRS) obtained using non-invasive continuous arterial pressure. Regardless of gestational and postnatal age, heart rate variability components (Ptot, VLF, LF, and HF) and baroreflex components (alpha LF, alpha HF and sBR) were found to be significantly lower in the RSV-infected group than in the control group (pimportance of maintaining prolonged cardiopulmonary monitoring. Copyright 2010 Elsevier B.V. All rights reserved.

  16. [Respiratory syncytial virus infections in children in general practice].

    Science.gov (United States)

    Nielsen, Lisa Monica; Halgrener, Jørgen; Hansen, Bjarne V Lühr

    2003-06-30

    The aim of the study was to describe the course of respiratory syncytial virus (RSV) infections in children under two years of age seen in general practice. Children under two years of age presenting acute respiratory infection during the registration period on 59 GPs' lists participated in the study. The GPs recorded data on a registration chart and a questionnaire was sent to the parents of the children in question one month after the date of inclusion. The children were tested in general practice for the presence of RSV. The GPs' objective findings and choice of treatment as well as the parents' account of the course of disease were compared in children with and without the presence of RSV. A total of 221 children participated in the study. Fifty-seven children were found RSV positive (25.8%). Among the RSV positive children there were significantly more with wheezing audibly detected with examination by stethoscope than among the RSV negative. The remaining parameters (the GP's objective examination, treatment and course of the disease) were distributed independently of the result of the RSV analysis. The results showed that RSV infections in children under two years in general practice are frequent and that the clinical picture most often is uncomplicated.

  17. Respiratory syncytial virus tracking using internet search engine data.

    Science.gov (United States)

    Oren, Eyal; Frere, Justin; Yom-Tov, Eran; Yom-Tov, Elad

    2018-04-03

    Respiratory Syncytial Virus (RSV) is the leading cause of hospitalization in children less than 1 year of age in the United States. Internet search engine queries may provide high resolution temporal and spatial data to estimate and predict disease activity. After filtering an initial list of 613 symptoms using high-resolution Bing search logs, we used Google Trends data between 2004 and 2016 for a smaller list of 50 terms to build predictive models of RSV incidence for five states where long-term surveillance data was available. We then used domain adaptation to model RSV incidence for the 45 remaining US states. Surveillance data sources (hospitalization and laboratory reports) were highly correlated, as were laboratory reports with search engine data. The four terms which were most often statistically significantly correlated as time series with the surveillance data in the five state models were RSV, flu, pneumonia, and bronchiolitis. Using our models, we tracked the spread of RSV by observing the time of peak use of the search term in different states. In general, the RSV peak moved from south-east (Florida) to the north-west US. Our study represents the first time that RSV has been tracked using Internet data results and highlights successful use of search filters and domain adaptation techniques, using data at multiple resolutions. Our approach may assist in identifying spread of both local and more widespread RSV transmission and may be applicable to other seasonal conditions where comprehensive epidemiological data is difficult to collect or obtain.

  18. A role for airway remodeling during respiratory syncytial virus infection

    Directory of Open Access Journals (Sweden)

    Dimina Dawn M

    2005-10-01

    Full Text Available Abstract Background Severe respiratory syncytial virus infection (RSV during infancy has been shown to be a major risk factor for the development of subsequent wheeze. However, the reasons for this link remain unclear. The objective of this research was to determine the consequences of early exposure to RSV and allergen in the development of subsequent airway hyperreactivity (AHR using a developmental time point in the mouse that parallels that of the human neonate. Methods Weanling mice were sensitized and challenged with ovalbumin (Ova and/or infected with RSV. Eight days after the last allergen challenge, various pathophysiological endpoints were examined. Results AHR in response to methacholine was enhanced only in weanling mice exposed to Ova and subsequently infected with RSV. The increase in AHR appeared to be unrelated to pulmonary RSV titer. Total bronchoalveolar lavage cellularity in these mice increased approximately two-fold relative to Ova alone and was attributable to increases in eosinophil and lymphocyte numbers. Enhanced pulmonary pathologies including persistent mucus production and subepithelial fibrosis were observed. Interestingly, these data correlated with transient increases in TNF-α, IFN-γ, IL-5, and IL-2. Conclusion The observed changes in pulmonary structure may provide an explanation for epidemiological data suggesting that early exposure to allergens and RSV have long-term physiological consequences. Furthermore, the data presented here highlight the importance of preventative strategies against RSV infection of atopic individuals during neonatal development.

  19. Sequential MRI, SPECT and PET in respiratory syncytial virus encephalitis

    International Nuclear Information System (INIS)

    Hirayama, K.; Sakazaki, Hiromi; Murakami, Seiko; Yonezawa, Sumiko; Fujimoto, Keiji; Seto, Toshiyuki; Tanaka, Katsuji; Hattori, Hideji; Matsuoka, Osamu; Murata, Ryosuke

    1999-01-01

    We report on a 3-year-old girl with respiratory syncytial virus (RSV) encephalitis manifested by disturbance of consciousness, conjugate eye deviation, anuria, truncal ataxia and intention tremor. T2-weighted magnetic resonance imaging (MRI) showed hyperintense areas in the cerebellar cortex. No lesion was detected in the cerebral cortex, pons or spinal cord. The hyperintense areas in the cerebellar cortex diminished with recovery from the clinical manifestations and had resolved 2 months after onset. The MRI lesions in the cerebellum were considered to be due to oedema. SPECT and positron emission tomography (PET), performed 3 months after onset, disclosed areas of hypoperfusion and hypometabolism at the same sites. One year after onset, MRI showed mild atrophy of the cerebellum. Hypoperfusion on SPECT and hypometabolism on PET remained. Neuroimaging showed that ataxia and tremor in this case were the result of cerebellitis. The patient has no neurological deficit except for mild truncal ataxia. This patient is a rare example of RSV encephalitis. (orig.)

  20. Occurrence of human respiratory syncytial virus in summer in Japan.

    Science.gov (United States)

    Shobugawa, Y; Takeuchi, T; Hibino, A; Hassan, M R; Yagami, R; Kondo, H; Odagiri, T; Saito, R

    2017-01-01

    In temperate zones, human respiratory syncytial virus (HRSV) outbreaks typically occur in cold weather, i.e. in late autumn and winter. However, recent outbreaks in Japan have tended to start during summer and autumn. This study examined associations of meteorological conditions with the numbers of HRSV cases reported in summer in Japan. Using data from the HRSV national surveillance system and national meteorological data for summer during the period 2007-2014, we utilized negative binomial logistic regression analysis to identify associations between meteorological conditions and reported cases of HRSV. HRSV cases increased when summer temperatures rose and when relative humidity increased. Consideration of the interaction term temperature × relative humidity enabled us to show synergistic effects of high temperature with HRSV occurrence. In particular, HRSV cases synergistically increased when relative humidity increased while the temperature was ⩾28·2 °C. Seasonal-trend decomposition analysis using the HRSV national surveillance data divided by 11 climate divisions showed that summer HRSV cases occurred in South Japan (Okinawa Island), Kyushu, and Nankai climate divisions, which are located in southwest Japan. Higher temperature and higher relative humidity were necessary conditions for HRSV occurrence in summer in Japan. Paediatricians in temperate zones should be mindful of possible HRSV cases in summer, when suitable conditions are present.

  1. PROPHYLACTIC ADMINISTRATION OF RESPIRATORY SYNCYTIAL VIRUS IMMUNE GLOBULIN TO HIGH-RISK INFANTS AND YOUNG-CHILDREN

    NARCIS (Netherlands)

    GROOTHUIS, [No Value; SIMOES, EAF; LEVIN, MJ; HALL, CB; LONG, CE; RODRIGUEZ, WJ; ARROBIO, J; MEISSNER, HC; FULTON, DR; WELLIVER, RC; TRISTRAM, DA; SIBER, GR; PRINCE, GA; VANRADEN, M; HEMMING, VG

    1993-01-01

    Background. Infants with cardiac disease or prematurity are at risk for severe illness caused by respiratory syncytial virus. Immune globulin with a high titer of antibodies against respiratory syncytial virus may offer infants and young children at risk protection from this serious, common

  2. Febrile status epilepticus due to respiratory syncytial virus infection.

    Science.gov (United States)

    Uda, Kazuhiro; Kitazawa, Katsuhiko

    2017-08-01

    Febrile status epilepticus can have neurological sequelae. The type of sequelae, however, depend on the etiology, including infection due to viral agents such as the influenza virus. Respiratory syncytial virus (RSV) infection in childhood may also contribute to this. The aim of this study was therefore to characterize febrile status epilepticus associated with RSV infection, and to determine whether this type of infection is a risk factor for neurological sequelae in febrile status epilepticus. We reviewed the medical records of children aged ≤3 years with febrile status epilepticus who were admitted to a tertiary hospital between January 2007 and December 2011. The differences between the RSV-positive and RSV-negative groups were evaluated according to the demographic and clinical data. A total of 99 patients with febrile status epilepticus who had been tested for RSV infection were identified. Three patients in the RSV-positive group (n = 19) and four in the RSV-negative group (n = 80) presented with bronchiolitis. The incidence of intubation and anti-seizure drug treatment in the RSV-positive group was significantly higher than in the -negative group. While all of the patients in the RSV-negative group recovered completely, six patients in the RSV-positive group developed encephalopathy and profound neurological sequelae. In five of the six patients, diffusion-weighted magnetic resonance imaging showed subcortical white matter lesions. RSV infection in the absence of bronchiolitis can initially present as febrile status epilepticus and subsequently develop into acute encephalopathy with profound neurological sequelae. © 2017 Japan Pediatric Society.

  3. Quantitative estimation of Nipah virus replication kinetics in vitro

    Directory of Open Access Journals (Sweden)

    Hassan Sharifah

    2006-06-01

    Full Text Available Abstract Background Nipah virus is a zoonotic virus isolated from an outbreak in Malaysia in 1998. The virus causes infections in humans, pigs, and several other domestic animals. It has also been isolated from fruit bats. The pathogenesis of Nipah virus infection is still not well described. In the present study, Nipah virus replication kinetics were estimated from infection of African green monkey kidney cells (Vero using the one-step SYBR® Green I-based quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR assay. Results The qRT-PCR had a dynamic range of at least seven orders of magnitude and can detect Nipah virus from as low as one PFU/μL. Following initiation of infection, it was estimated that Nipah virus RNA doubles at every ~40 minutes and attained peak intracellular virus RNA level of ~8.4 log PFU/μL at about 32 hours post-infection (PI. Significant extracellular Nipah virus RNA release occurred only after 8 hours PI and the level peaked at ~7.9 log PFU/μL at 64 hours PI. The estimated rate of Nipah virus RNA released into the cell culture medium was ~0.07 log PFU/μL per hour and less than 10% of the released Nipah virus RNA was infectious. Conclusion The SYBR® Green I-based qRT-PCR assay enabled quantitative assessment of Nipah virus RNA synthesis in Vero cells. A low rate of Nipah virus extracellular RNA release and low infectious virus yield together with extensive syncytial formation during the infection support a cell-to-cell spread mechanism for Nipah virus infection.

  4. Genetic and antigenic analysis of the G attachment protein of bovine respiratory syncytial virus strains

    DEFF Research Database (Denmark)

    Elvander, M.; Vilcek, S.; Baule, C.

    1998-01-01

    Antigenic and genetic studies of bovine respiratory syncytial virus (BRSV) were made on isolates obtained from three continents over 27 years. Antigenic variation between eight isolates was initially determined using protein G-specific monoclonal antibodies. Four distinct reaction patterns were...... of a 731 nucleotide fragment in the G protein gene. Nine of the BRSV strains were analysed by direct sequencing of RT-PCR amplicons whereas sequences of 18 BRSV and three human respiratory syncytial virus (HRSV) strains were obtained from GenBank. The analysis revealed similarities of 88-100% among BRSV...

  5. Human airway epithelial cell cultures for modeling respiratory syncytial virus infection.

    Science.gov (United States)

    Pickles, Raymond J

    2013-01-01

    Respiratory syncytial virus (RSV) is an important human respiratory pathogen with narrow species tropism. Limited availability of human pathologic specimens during early RSV-induced lung disease and ethical restrictions for RSV challenge studies in the lower airways of human volunteers has slowed our understanding of how RSV causes airway disease and greatly limited the development of therapeutic strategies for reducing RSV disease burden. Our current knowledge of RSV infection and pathology is largely based on in vitro studies using nonpolarized epithelial cell-lines grown on plastic or in vivo studies using animal models semipermissive for RSV infection. Although these models have revealed important aspects of RSV infection, replication, and associated inflammatory responses, these models do not broadly recapitulate the early interactions and potential consequences of RSV infection of the human columnar airway epithelium in vivo. In this chapter, the pro et contra of in vitro models of human columnar airway epithelium and their usefulness in respiratory virus pathogenesis and vaccine development studies will be discussed. The use of such culture models to predict characteristics of RSV infection and the correlation of these findings to the human in vivo situation will likely accelerate our understanding of RSV pathogenesis potentially identifying novel strategies for limiting the severity of RSV-associated airway disease.

  6. Global respiratory syncytial virus-associated mortality in young children (RSV GOLD) : a retrospective case series

    NARCIS (Netherlands)

    Scheltema, Nienke M.; Gentile, Angela; Lucion, Florencia; Nokes, D. James; Munywoki, Patrick K.; Madhi, Shabir A.; Groome, Michelle J; Cohen, Cheryl; Moyes, Jocelyn; Thorburn, Kentigern; Thamthitiwat, Somsak; Oshitani, Hitoshi; Lupisan, Socorro P.; Gordon, Aubree; Sánchez, José F.; O'Brien, Katherine L.; Gessner, Bradford D.; Sutanto, Agustinus; Mejias, Asuncion; Ramilo, Octavio; Khuri-Bulos, Najwa; Halasa, Natasha; de-Paris, Fernanda; Pires, Márcia Rosane; Spaeder, Michael C.; Paes, Bosco A.; Simões, Eric A F; Leung, Ting F.; da Costa Oliveira, Maria Tereza; de Freitas Lázaro Emediato, Carla Cecília; Bassat, Quique; Butt, Warwick; Chi, Hsin; Aamir, Uzma Bashir; Ali, Asad; Lucero, Marilla G.; Fasce, Rodrigo A.; Lopez, Olga; Rath, Barbara A.; Polack, Fernando P.; Papenburg, Jesse; Roglić, Srđan; Ito, Hisato; Goka, Edward A.; Grobbee, Diederick E.; Nair, Harish; Bont, Louis J.

    2017-01-01

    Background Respiratory syncytial virus (RSV) infection is an important cause of pneumonia mortality in young children. However, clinical data for fatal RSV infection are scarce. We aimed to identify clinical and socioeconomic characteristics of children aged younger than 5 years with RSV-related

  7. Reduced Expression of HLA-DR on Monocytes During Severe Respiratory Syncytial Virus Infections

    NARCIS (Netherlands)

    Ahout, I.M.L.; Jans, J.; Haroutiounian, L.; Simonetti, E.R.; Gaast-de Jongh, C.E. van der; Diavatopoulos, D.A.; Jonge, M.I. de; Groot, R. de; Ferwerda, G.

    2016-01-01

    BACKGROUND: Respiratory syncytial virus (RSV) is a common cause of bronchiolitis in infants with a wide spectrum of disease severity. Besides environmental and genetic factors, it is thought that the innate immune system plays a pivotal role. The aim of this study was to investigate the expression

  8. Chronic diseases, chromosomal abnormalities, and congenital malformations as risk factors for respiratory syncytial virus hospitalization

    DEFF Research Database (Denmark)

    Kristensen, Kim; Hjuler, Thomas; Ravn, Henrik

    2012-01-01

    Little is known about how chronic conditions other than prematurity, heart disease, and Down syndrome affect the risk and severity of hospitalization for respiratory syncytial virus (RSV). We assess the risk and severity of RSV hospitalization in children with chronic conditions in this register...

  9. Seasonality of long term wheezing following respiratory syncytial virus lower respiratory tract infection

    NARCIS (Netherlands)

    Bont, L.; Steijn, M.; van Aalderen, W. M. C.; Brus, F.; Th Draaisma, J. M.; van Diemen-Steenvoorde, R. A. A. M.; Pekelharing-Berghuis, M.; Kimpen, J. L. L.

    2004-01-01

    Background: It is well known that respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) is associated with subsequent wheezing episodes, but the precise natural course of wheezing following RSV LRTI is not known. This study aimed to determine the continuous development of

  10. Seasonality of long term wheezing following respiratory syncytial virus lower respiratory tract infection

    NARCIS (Netherlands)

    Bont, L; Steijn, M; van Aalderen, WMC; Brus, F; Draaisma, JMT; Van Diemen-Steenvoorde, RAAM; Pekelharing-Berghuis, M; Kimpen, JLL

    Background: It is well known that respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) is associated with subsequent wheezing episodes, but the precise natural course of wheezing following RSV LRTI is not known. This study aimed to determine the continuous development of

  11. Heliox reduces respiratory system resistance in respiratory syncytial virus induced respiratory failure

    NARCIS (Netherlands)

    Kneyber, Martin C. J.; van Heerde, Marc; Twisk, Jos W. R.; Plotz, Frans B.; Markhors, Dick G.

    2009-01-01

    Introduction Respiratory syncytial virus (RSV) lower respiratory tract disease is characterised by narrowing of the airways resulting in increased airway resistance, air-trapping and respiratory acidosis. These problems might be overcome using helium-oxygen gas mixture. However, the effect of

  12. Radiological findings in children with respiratory syncytial virus infection: Relationship to clinical and bacteriological findings

    International Nuclear Information System (INIS)

    Eriksson, J.; Nordshus, T.; Westvik, J.; Carlsen, K.H.; Oerstadvik, I.; Eng, J.

    1986-01-01

    Respiratory syncytial virus (RSV) is a frequent cause of bronchiolitis leading to acute admission to hospital in the winter months. A wide range of findings accompanies this disease and the appearances are seldom completely diagnostic. Associated bacterial co-infections are common and we have shown an association with atelectasis among patients with pathogenic bacteria in the nasopharynx. (orig.)

  13. Heliox reduces respiratory system resistance in respiratory syncytial virus induced respiratory failure

    NARCIS (Netherlands)

    Kneijber, M.C.J.; van Heerde, M.; Twisk, J.W.R.; Plotz, F.; Markhorst, D.G.

    2009-01-01

    Introduction: Respiratory syncytial virus (RSV) lower respiratory tract disease is characterised by narrowing of the airways resulting in increased airway resistance, air-trapping and respiratory acidosis. These problems might be overcome using helium-oxygen gas mixture. However, the effect of

  14. Radiological features of lower respiratory infection by respiratory syncytial virus in infants and young children

    International Nuclear Information System (INIS)

    Kim, Woo Sun; Kim, In One; Yeon, Kyung Mo; Jang, Seong Hee; Lee, Hoan Jong

    1992-01-01

    Respiratory syncytial virus is the most common cause of lower respiratory infection (bronchiolitis and pneumonia) of infancy and early childhood. We analyzed clinical and radiological features of 76 patients with lower respiratory infections by respiratory syncytial virus, which were diagnosed by indirect immunofluorescent test or culture of nasal aspirate in Hep-2-cell monolayer, during the period of January- December, 1991. There were peaks of incidences in March-May and November- December, accounting for 87% of eases. Sixty-two cases (82%) were under 1 year of age. Fifty cases (66%) had underlying diseases. Major radiographical findings were overaeration (83%), parahilar peribronchial infiltrates (67%), segmental or subsegmental atelectasis (32%), and segmental or lobar consolidation (16%). In 15 cases (20%), overaeration was the only radiological findings. There was no evidence of pleural effusion or lymph node enlargement in all cases. By considering clinical features (symptoms, age, underlying diseases, epidemic seasons) in addition to the radiological findings, radiologists would be familiar with lower respiratory infection by respiratory syncytial virus. Air space consolidation, which is generally thought to represent bacterial pneumonia, is also observed not infrequently in respiratory syncytial virus infection

  15. Incidence and seasonality of respiratory syncytial virus hospitalisations in young children in Denmark, 2010 to 2015

    DEFF Research Database (Denmark)

    Jepsen, Martin T; Trebbien, Ramona; Emborg, Hanne Dorthe

    2018-01-01

    For future decisions on respiratory syncytial virus (RSV)-vaccination strategies and implementation into national immunisation-programmes, we used national registry data (hospitalisation, microbiology and vital statistics) to determine the age-specific incidence and direct medical costs of annual...

  16. Lower respiratory tract infection caused by respiratory syncytial virus : current management and new therapeutics

    NARCIS (Netherlands)

    Mazur, Natalie; Martinon-Torres, Federico; Baraldi, Eugenio; Fauroux, Brigitte; Greenough, Anne; Heikkinen, Terho; Manzoni, Paolo; Mejias, Asuncion; Nair, Harish; Papadopoulos, Nikolaos G.; Polack, Fernando P.; Ramilo, Octavio; Sharland, Mike; Stein, Renato; Madhi, Shabir A.; Bont, Louis

    2015-01-01

    Respiratory syncytial virus (RSV) is a major worldwide cause of morbidity and mortality in children under five years of age. Evidence-based management guidelines suggest that there is no effective treatment for RSV lower respiratory tract infection (LRTI) and that supportive care, ie, hydration and

  17. An ultrastructural study of the interaction of human eosinophils with respiratory syncytial virus

    NARCIS (Netherlands)

    Kimpen, JLL; Garofalo, R; Welliver, RC; Fujihara, K; Ogra, PL

    It was shown previously that eosinophils are activated in vivo and in vitro by respiratory syncytial virus (RSV) (Garofalo et al., J Pediatr 1992: 120: 28-32; Kimpen et al., Pediatr Res 1992: 32: 160-4). For study of the interaction of eosinophils and RSV on the ultrastructural level, normodense

  18. Pericarditis mediated by respiratory syncytial virus in a hematopoietic stem cell transplant patient.

    Science.gov (United States)

    Rubach, M P; Pavlisko, E N; Perfect, J R

    2013-08-01

    We describe a case of pericarditis and large pericardial effusion in a 63-year-old African-American man undergoing autologous hematopoietic stem cell transplant for multiple myeloma. Pericardial tissue biopsy demonstrated fibrinous pericarditis, and immunohistochemistry stains were positive for respiratory syncytial virus. The patient improved with oral ribavirin and intravenous immune globulin infusions. © 2013 John Wiley & Sons A/S.

  19. Effect of compounds with antibacterial activities in human milk on respiratory syncytial virus and cytomegalovirus in vitro.

    Science.gov (United States)

    Portelli, J; Gordon, A; May, J T

    1998-11-01

    The effect of some antibacterial compounds present in human milk were tested for antiviral activity against respiratory syncytial virus, Semliki Forest virus and cytomegalovirus. These included the gangliosides GM1, GM2 and GM3, sialyl-lactose, lactoferrin and chondroitin sulphate A, B and C, which were all tested for their ability to inhibit the viruses in cell culture. Of the compounds tested, only the ganglioside GM2, chondroitin sulphate B and lactoferrin inhibited the absorption and growth of respiratory syncytial virus in cell culture, and none inhibited the growth of Semliki Forest virus, indicating that lipid antiviral activity was not associated with any of the gangliosides. While the concentrations of these two compounds required to inhibit respiratory syncytial virus were in excess of those present in human milk, sialyl-lactose concentrations similar to those present in human milk increased the growth of cytomegalovirus. Lactoferrin was confirmed as inhibiting both respiratory syncytial virus and cytomegalovirus growth in culture even when used at lower concentrations than those present in human milk. The antiviral activities of GM2, chondroitin sulphate B and lactoferrin were tested when added to an infant formula. Lactoferrin continued to have antiviral activity against cytomegalovirus, but a lower activity against respiratory syncytial virus; ganglioside GM2 and chondroitin sulphate B still maintained antiviral activity against respiratory syncytial virus.

  20. Ferrets as a Novel Animal Model for Studying Human Respiratory Syncytial Virus Infections in Immunocompetent and Immunocompromised Hosts

    Science.gov (United States)

    Stittelaar, Koert J.; de Waal, Leon; van Amerongen, Geert; Veldhuis Kroeze, Edwin J.B.; Fraaij, Pieter L.A.; van Baalen, Carel A.; van Kampen, Jeroen J.A.; van der Vries, Erhard; Osterhaus, Albert D.M.E.; de Swart, Rik L.

    2016-01-01

    Human respiratory syncytial virus (HRSV) is an important cause of severe respiratory tract disease in immunocompromised patients. Animal models are indispensable for evaluating novel intervention strategies in this complex patient population. To complement existing models in rodents and non-human primates, we have evaluated the potential benefits of an HRSV infection model in ferrets (Mustela putorius furo). Nine- to 12-month-old HRSV-seronegative immunocompetent or immunocompromised ferrets were infected with a low-passage wild-type strain of HRSV subgroup A (105 TCID50) administered by intra-tracheal or intra-nasal inoculation. Immune suppression was achieved by bi-daily oral administration of tacrolimus, mycophenolate mofetil, and prednisolone. Throat and nose swabs were collected daily and animals were euthanized four, seven, or 21 days post-infection (DPI). Virus loads were determined by quantitative virus culture and qPCR. We observed efficient HRSV replication in both the upper and lower respiratory tract. In immunocompromised ferrets, virus loads reached higher levels and showed delayed clearance as compared to those in immunocompetent animals. Histopathological evaluation of animals euthanized 4 DPI demonstrated that the virus replicated in the respiratory epithelial cells of the trachea, bronchi, and bronchioles. These animal models can contribute to an assessment of the efficacy and safety of novel HRSV intervention strategies. PMID:27314379

  1. Ferrets as a Novel Animal Model for Studying Human Respiratory Syncytial Virus Infections in Immunocompetent and Immunocompromised Hosts

    Directory of Open Access Journals (Sweden)

    Koert J. Stittelaar

    2016-06-01

    Full Text Available Human respiratory syncytial virus (HRSV is an important cause of severe respiratory tract disease in immunocompromised patients. Animal models are indispensable for evaluating novel intervention strategies in this complex patient population. To complement existing models in rodents and non-human primates, we have evaluated the potential benefits of an HRSV infection model in ferrets (Mustela putorius furo. Nine- to 12-month-old HRSV-seronegative immunocompetent or immunocompromised ferrets were infected with a low-passage wild-type strain of HRSV subgroup A (105 TCID50 administered by intra-tracheal or intra-nasal inoculation. Immune suppression was achieved by bi-daily oral administration of tacrolimus, mycophenolate mofetil, and prednisolone. Throat and nose swabs were collected daily and animals were euthanized four, seven, or 21 days post-infection (DPI. Virus loads were determined by quantitative virus culture and qPCR. We observed efficient HRSV replication in both the upper and lower respiratory tract. In immunocompromised ferrets, virus loads reached higher levels and showed delayed clearance as compared to those in immunocompetent animals. Histopathological evaluation of animals euthanized 4 DPI demonstrated that the virus replicated in the respiratory epithelial cells of the trachea, bronchi, and bronchioles. These animal models can contribute to an assessment of the efficacy and safety of novel HRSV intervention strategies.

  2. Respiratory syncytial virus M2-1 protein induces the activation of nuclear factor kappa B

    Energy Technology Data Exchange (ETDEWEB)

    Reimers, Kerstin [Klinik fuer Plastische, Hand-und Wiederherstellungschirurgie, Podbielskistrasse 380, D-30659 Hannover (Germany); Buchholz, Katja [Institut fuer Medizinische Mikrobiologie, Otto-von-Guericke-Universitaet Magdeburg, Leipzigerstrasse 44, D-39120 Magdeburg (Germany); Werchau, Hermann [Institut fuer Medizinische Mikrobiologie, Otto-von-Guericke-Universitaet Magdeburg, Leipzigerstrasse 44, D-39120 Magdeburg (Germany)

    2005-01-20

    Respiratory syncytial virus (RSV) induces the production of a number of cytokines and chemokines by activation of nuclear factor kappa B (NF-{kappa}B). The activation of NF-{kappa}B has been shown to depend on viral replication in the infected cells. In this study, we demonstrate that expression of RSV M2-1 protein, a transcriptional processivity and anti-termination factor, is sufficient to activate NF-{kappa}B in A549 cells. Electromobility shift assays show increased NF-{kappa}B complexes in the nuclei of M2-1-expressing cells. M2-1 protein is found in nuclei of M2-1-expressing cells and in RSV-infected cells. Co-immunoprecipitations of nuclear extracts of M2-1-expressing cells and of RSV-infected cells revealed an association of M2-1 with Rel A protein. Furthermore, the activation of NF-{kappa}B depends on the C-terminus of the RSV M2-1 protein, as shown by NF-{kappa}B-induced gene expression of a reporter gene construct.

  3. Serological indication for persistence of bovine respiratory syncytial virus in cattle and attempts to detect the virus

    NARCIS (Netherlands)

    Poel, van der W.H.M.; Langedijk, J.P.M.; Kramps, J.A.; Middel, W.G.J.; Brand, A.; Oirschot, van J.T.

    1997-01-01

    To identify putative persistent bovine respiratory syncytial virus (BRSV) infections in cattle, seven cattle that had experienced BRSV infections were treated with corticosteroids for two periods of 5 days. During the 5-day periods and the 3 weeks after treatment, attempts were made to isolate BRSV

  4. Sub-nucleocapsid nanoparticles: a nasal vaccine against respiratory syncytial virus.

    Directory of Open Access Journals (Sweden)

    Xavier Roux

    Full Text Available BACKGROUND: Bronchiolitis caused by the respiratory syncytial virus (RSV in infants less than two years old is a growing public health concern worldwide, and there is currently no safe and effective vaccine. A major component of RSV nucleocapsid, the nucleoprotein (N, has been so far poorly explored as a potential vaccine antigen, even though it is a target of protective anti-viral T cell responses and is remarkably conserved between human RSV A and B serotypes. We recently reported a method to produce recombinant N assembling in homogenous rings composed of 10-11 N subunits enclosing a bacterial RNA. These nanoparticles were named sub-nucleocapsid ring structure (N SRS. METHODOLOGY AND PRINCIPAL FINDINGS: The vaccine potential of N SRS was evaluated in a well-characterized and widely acknowledged mouse model of RSV infection. BALB/c adult mice were immunized intranasally with N SRS adjuvanted with the detoxified E. coli enterotoxin LT(R192G. Upon RSV challenge, vaccinated mice were largely protected against virus replication in the lungs, with a mild inflammatory lymphocytic and neutrophilic reaction in their airways. Mucosal immunization with N SRS elicited strong local and systemic immunity characterized by high titers of IgG1, IgG2a and IgA anti-N antibodies, antigen-specific CD8(+ T cells and IFN-gamma-producing CD4(+ T cells. CONCLUSIONS/SIGNIFICANCE: This is the first report of using nanoparticles formed by the recombinant nucleocapsid protein as an efficient and safe intra-nasal vaccine against RSV.

  5. Macrophages are required for dendritic cell uptake of respiratory syncytial virus from an infected epithelium.

    Science.gov (United States)

    Ugonna, Kelechi; Bingle, Colin D; Plant, Karen; Wilson, Kirsty; Everard, Mark L

    2014-01-01

    We have previously shown that the respiratory syncytial virus [RSV] can productively infect monocyte derived dendritic cells [MoDC] and remain dormant within the same cells for prolonged periods. It is therefore possible that infected dendritic cells act as a reservoir within the airways of individuals between annual epidemics. In the present study we explored the possibility that sub-epithelial DCs can be infected with RSV from differentiated bronchial epithelium and that in turn RSV from DCs can infect the epithelium. A dual co-culture model was established in which a differentiated primary airway epithelium on an Air Liquid Interface (ALI) was cultured on a transwell insert and MoDCs were subsequently added to the basolateral membrane of the insert. Further experiments were undertaken using a triple co-culture model in which in which macrophages were added to the apical surface of the differentiated epithelium. A modified RSV [rr-RSV] expressing a red fluorescent protein marker of replication was used to infect either the MoDCs or the differentiated epithelium and infection of the reciprocal cell type was assessed using confocal microscopy. Our data shows that primary epithelium became infected when rr-RSV infected MoDCs were introduced onto the basal surface of the transwell insert. MoDCs located beneath the epithelium did not become infected with virus from infected epithelial cells in the dual co-culture model. However when macrophages were present on the apical surface of the primary epithelium infection of the basal MoDCs occurred. Our data suggests that RSV infected dendritic cells readily transmit infection to epithelial cells even when they are located beneath the basal layer. However macrophages appear to be necessary for the transmission of infection from epithelial cells to basal dendritic cells.

  6. A Randomized Placebo Controlled Trial of Ibuprofen for Respiratory Syncytial Virus Infection in a Bovine Model.

    Directory of Open Access Journals (Sweden)

    Paul Walsh

    Full Text Available Respiratory syncytial virus (RSV is the most common cause of bronchiolitis and hospital admission in infants. An analogous disease occurs in cattle and costs US agriculture a billion dollars a year. RSV causes much of its morbidity indirectly via adverse effects of the host response to the virus. RSV is accompanied by elevated prostaglandin E2 (PGE2 which is followed by neutrophil led inflammation in the lung. Ibuprofen is a prototypical non-steroidal anti-inflammatory drug that decreases PGE2 levels by inhibiting cyclooxygenase.We hypothesized that treatment of RSV with ibuprofen would decrease PGE2 levels, modulate the immune response, decrease clinical illness, and decrease the histopathological lung changes in a bovine model of RSV. We further hypothesized that viral replication would be unaffected.We performed a randomized placebo controlled trial of ibuprofen in 16 outbred Holstein calves that we infected with RSV. We measured clinical scores, cyclooxygenase, lipoxygenase and endocannabinoid products in plasma and mediastinal lymph nodes and interleukin (Il-4, Il-13, Il-17 and interferon-γ in mediastinal lymph nodes. RSV shedding was measured daily and nasal Il-6, Il-8 and Il-17 every other day. The calves were necropsied on Day 10 post inoculation and histology performed.One calf in the ibuprofen group required euthanasia on Day 8 of infection for respiratory distress. Clinical scores (p<0.01 and weight gain (p = 0.08 seemed better in the ibuprofen group. Ibuprofen decreased cyclooxygenase, lipoxygenase, and cytochrome P450 products, and increased monoacylglycerols in lung lymph nodes. Ibuprofen modulated the immune response as measured by narrowed range of observed Il-13, Il-17 and IFN-γ gene expression in mediastinal lymph nodes. Lung histology was not different between groups, and viral shedding was increased in calves randomized to ibuprofen.Ibuprofen decreased PGE2, modulated the immune response, and improved clinical outcomes

  7. A Randomized Placebo Controlled Trial of Ibuprofen for Respiratory Syncytial Virus Infection in a Bovine Model

    Science.gov (United States)

    Walsh, Paul; Behrens, Nicole; Carvallo Chaigneau, Francisco R.; McEligot, Heather; Agrawal, Karan; Newman, John W.; Anderson, Mark; Gershwin, Laurel J.

    2016-01-01

    Background Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis and hospital admission in infants. An analogous disease occurs in cattle and costs US agriculture a billion dollars a year. RSV causes much of its morbidity indirectly via adverse effects of the host response to the virus. RSV is accompanied by elevated prostaglandin E2 (PGE2) which is followed by neutrophil led inflammation in the lung. Ibuprofen is a prototypical non-steroidal anti-inflammatory drug that decreases PGE2 levels by inhibiting cyclooxygenase. Hypotheses We hypothesized that treatment of RSV with ibuprofen would decrease PGE2 levels, modulate the immune response, decrease clinical illness, and decrease the histopathological lung changes in a bovine model of RSV. We further hypothesized that viral replication would be unaffected. Methods We performed a randomized placebo controlled trial of ibuprofen in 16 outbred Holstein calves that we infected with RSV. We measured clinical scores, cyclooxygenase, lipoxygenase and endocannabinoid products in plasma and mediastinal lymph nodes and interleukin (Il)-4, Il-13, Il-17 and interferon-γ in mediastinal lymph nodes. RSV shedding was measured daily and nasal Il-6, Il-8 and Il-17 every other day. The calves were necropsied on Day 10 post inoculation and histology performed. Results One calf in the ibuprofen group required euthanasia on Day 8 of infection for respiratory distress. Clinical scores (pibuprofen group. Ibuprofen decreased cyclooxygenase, lipoxygenase, and cytochrome P450 products, and increased monoacylglycerols in lung lymph nodes. Ibuprofen modulated the immune response as measured by narrowed range of observed Il-13, Il-17 and IFN-γ gene expression in mediastinal lymph nodes. Lung histology was not different between groups, and viral shedding was increased in calves randomized to ibuprofen. Conclusions Ibuprofen decreased PGE2, modulated the immune response, and improved clinical outcomes. However lung

  8. Antibody-Induced Internalization of the Human Respiratory Syncytial Virus Fusion Protein.

    Science.gov (United States)

    Leemans, A; De Schryver, M; Van der Gucht, W; Heykers, A; Pintelon, I; Hotard, A L; Moore, M L; Melero, J A; McLellan, J S; Graham, B S; Broadbent, L; Power, U F; Caljon, G; Cos, P; Maes, L; Delputte, P

    2017-07-15

    Respiratory syncytial virus (RSV) infections remain a major cause of respiratory disease and hospitalizations among infants. Infection recurs frequently and establishes a weak and short-lived immunity. To date, RSV immunoprophylaxis and vaccine research is mainly focused on the RSV fusion (F) protein, but a vaccine remains elusive. The RSV F protein is a highly conserved surface glycoprotein and is the main target of neutralizing antibodies induced by natural infection. Here, we analyzed an internalization process of antigen-antibody complexes after binding of RSV-specific antibodies to RSV antigens expressed on the surface of infected cells. The RSV F protein and attachment (G) protein were found to be internalized in both infected and transfected cells after the addition of either RSV-specific polyclonal antibodies (PAbs) or RSV glycoprotein-specific monoclonal antibodies (MAbs), as determined by indirect immunofluorescence staining and flow-cytometric analysis. Internalization experiments with different cell lines, well-differentiated primary bronchial epithelial cells (WD-PBECs), and RSV isolates suggest that antibody internalization can be considered a general feature of RSV. More specifically for RSV F, the mechanism of internalization was shown to be clathrin dependent. All RSV F-targeted MAbs tested, regardless of their epitopes, induced internalization of RSV F. No differences could be observed between the different MAbs, indicating that RSV F internalization was epitope independent. Since this process can be either antiviral, by affecting virus assembly and production, or beneficial for the virus, by limiting the efficacy of antibodies and effector mechanism, further research is required to determine the extent to which this occurs in vivo and how this might impact RSV replication. IMPORTANCE Current research into the development of new immunoprophylaxis and vaccines is mainly focused on the RSV F protein since, among others, RSV F-specific antibodies are

  9. Extensive sequence divergence among bovine respiratory syncytial viruses isolated during recurrent outbreaks in closed herds

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Tjørnehøj, Kirsten; Viuff, B.

    2000-01-01

    and veal calf production units) in different years and from all confirmed outbreaks in Denmark within a short period. The results showed that identical viruses were isolated within a herd during outbreaks and that viruses from recurrent infections varied by up to 11% in sequence even in closed herds......The nucleotides coding for the extracellular part of the G glycoprotein and the full SH protein of bovine respiratory syncytial virus (BRSV) were sequenced from viruses isolated from numerous outbreaks of BRSV infection. The isolates included viruses isolated from the same herd (closed dairy farms....... It is possible that a quasispecies variant swarm of BRSV persisted in some of the calves in each herd and that a new and different highly fit virus type (master and consensus sequence) became dominant and spread from a single animal in connection with each new outbreak. Based on the high level of diversity...

  10. Ultrastructural Characterization of Zika Virus Replication Factories

    Directory of Open Access Journals (Sweden)

    Mirko Cortese

    2017-02-01

    Full Text Available Summary: A global concern has emerged with the pandemic spread of Zika virus (ZIKV infections that can cause severe neurological symptoms in adults and newborns. ZIKV is a positive-strand RNA virus replicating in virus-induced membranous replication factories (RFs. Here we used various imaging techniques to investigate the ultrastructural details of ZIKV RFs and their relationship with host cell organelles. Analyses of human hepatic cells and neural progenitor cells infected with ZIKV revealed endoplasmic reticulum (ER membrane invaginations containing pore-like openings toward the cytosol, reminiscent to RFs in Dengue virus-infected cells. Both the MR766 African strain and the H/PF/2013 Asian strain, the latter linked to neurological diseases, induce RFs of similar architecture. Importantly, ZIKV infection causes a drastic reorganization of microtubules and intermediate filaments forming cage-like structures surrounding the viral RF. Consistently, ZIKV replication is suppressed by cytoskeleton-targeting drugs. Thus, ZIKV RFs are tightly linked to rearrangements of the host cell cytoskeleton. : Cortese et al. show that ZIKV infection in both human hepatoma and neuronal progenitor cells induces drastic structural modification of the cellular architecture. Microtubules and intermediate filaments surround the viral replication factory composed of vesicles corresponding to ER membrane invagination toward the ER lumen. Importantly, alteration of microtubule flexibility impairs ZIKV replication. Keywords: Zika virus, flavivirus, human neural progenitor cells, replication factories, replication organelles, microtubules, intermediate filaments, electron microscopy, electron tomography, live-cell imaging

  11. Generation and Characterization of ALX-0171, a Potent Novel Therapeutic Nanobody for the Treatment of Respiratory Syncytial Virus Infection

    Science.gov (United States)

    Stohr, Thomas; Palomo, Concepción; Piedra, Pedro A.; Gilbert, Brian E.; Mas, Vicente; Millar, Andrena; Power, Ultan F.; Stortelers, Catelijne; Allosery, Koen; Melero, José A.; Depla, Erik

    2015-01-01

    Respiratory syncytial virus (RSV) is an important causative agent of lower respiratory tract infections in infants and elderly individuals. Its fusion (F) protein is critical for virus infection. It is targeted by several investigational antivirals and by palivizumab, a humanized monoclonal antibody used prophylactically in infants considered at high risk of severe RSV disease. ALX-0171 is a trimeric Nanobody that binds the antigenic site II of RSV F protein with subnanomolar affinity. ALX-0171 demonstrated in vitro neutralization superior to that of palivizumab against prototypic RSV subtype A and B strains. Moreover, ALX-0171 completely blocked replication to below the limit of detection for 87% of the viruses tested, whereas palivizumab did so for 18% of the viruses tested at a fixed concentration. Importantly, ALX-0171 was highly effective in reducing both nasal and lung RSV titers when delivered prophylactically or therapeutically directly to the lungs of cotton rats. ALX-0171 represents a potent novel antiviral compound with significant potential to treat RSV-mediated disease. PMID:26438495

  12. The viral transcription group determines the HLA class I cellular immune response against human respiratory syncytial virus.

    Science.gov (United States)

    Johnstone, Carolina; Lorente, Elena; Barriga, Alejandro; Barnea, Eilon; Infantes, Susana; Lemonnier, François A; David, Chella S; Admon, Arie; López, Daniel

    2015-04-01

    The cytotoxic T-lymphocyte-mediated killing of virus-infected cells requires previous recognition of short viral antigenic peptides bound to human leukocyte antigen class I molecules that are exposed on the surface of infected cells. The cytotoxic T-lymphocyte response is critical for the clearance of human respiratory syncytial virus infection. In this study, naturally processed viral human leukocyte antigen class I ligands were identified with mass spectrometry analysis of complex human leukocyte antigen-bound peptide pools isolated from large amounts of human respiratory syncytial virus-infected cells. Acute antiviral T-cell response characterization showed that viral transcription determines both the immunoprevalence and immunodominance of the human leukocyte antigen class I response to human respiratory syncytial virus. These findings have clear implications for antiviral vaccine design. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. The Viral Transcription Group Determines the HLA Class I Cellular Immune Response Against Human Respiratory Syncytial Virus*

    Science.gov (United States)

    Johnstone, Carolina; Lorente, Elena; Barriga, Alejandro; Barnea, Eilon; Infantes, Susana; Lemonnier, François A.; David, Chella S.; Admon, Arie; López, Daniel

    2015-01-01

    The cytotoxic T-lymphocyte-mediated killing of virus-infected cells requires previous recognition of short viral antigenic peptides bound to human leukocyte antigen class I molecules that are exposed on the surface of infected cells. The cytotoxic T-lymphocyte response is critical for the clearance of human respiratory syncytial virus infection. In this study, naturally processed viral human leukocyte antigen class I ligands were identified with mass spectrometry analysis of complex human leukocyte antigen-bound peptide pools isolated from large amounts of human respiratory syncytial virus-infected cells. Acute antiviral T-cell response characterization showed that viral transcription determines both the immunoprevalence and immunodominance of the human leukocyte antigen class I response to human respiratory syncytial virus. These findings have clear implications for antiviral vaccine design. PMID:25635267

  14. Archaeal Viruses: Diversity, Replication, and Structure.

    Science.gov (United States)

    Dellas, Nikki; Snyder, Jamie C; Bolduc, Benjamin; Young, Mark J

    2014-11-01

    The Archaea-and their viruses-remain the most enigmatic of life's three domains. Once thought to inhabit only extreme environments, archaea are now known to inhabit diverse environments. Even though the first archaeal virus was described over 40 years ago, only 117 archaeal viruses have been discovered to date. Despite this small number, these viruses have painted a portrait of enormous morphological and genetic diversity. For example, research centered around the various steps of the archaeal virus life cycle has led to the discovery of unique mechanisms employed by archaeal viruses during replication, maturation, and virion release. In many instances, archaeal virus proteins display very low levels of sequence homology to other proteins listed in the public database, and therefore, structural characterization of these proteins has played an integral role in functional assignment. These structural studies have not only provided insights into structure-function relationships but have also identified links between viruses across all three domains of life.

  15. A Model of the Costs of Community and Nosocomial Pediatric Respiratory Syncytial Virus Infections in Canadian Hospitals

    Directory of Open Access Journals (Sweden)

    Philip Jacobs

    2013-01-01

    Full Text Available BACKGROUND: Approximately one in 10 hospitalized patients will acquire a nosocomial infection (NI after admission to hospital, of which 71% are due to respiratory viruses, including the respiratory syncytial virus (RSV. NIs are concerning and lead to prolonged hospitalizations. The economics of NIs are typically described in generalized terms and specific cost data are lacking.

  16. The molecular biology of Bluetongue virus replication.

    Science.gov (United States)

    Patel, Avnish; Roy, Polly

    2014-03-01

    The members of Orbivirus genus within the Reoviridae family are arthropod-borne viruses which are responsible for high morbidity and mortality in ruminants. Bluetongue virus (BTV) which causes disease in livestock (sheep, goat, cattle) has been in the forefront of molecular studies for the last three decades and now represents the best understood orbivirus at a molecular and structural level. The complex nature of the virion structure has been well characterised at high resolution along with the definition of the virus encoded enzymes required for RNA replication; the ordered assembly of the capsid shell as well as the protein and genome sequestration required for it; and the role of host proteins in virus entry and virus release. More recent developments of Reverse Genetics and Cell-Free Assembly systems have allowed integration of the accumulated structural and molecular knowledge to be tested at meticulous level, yielding higher insight into basic molecular virology, from which the rational design of safe efficacious vaccines has been possible. This article is centred on the molecular dissection of BTV with a view to understanding the role of each protein in the virus replication cycle. These areas are important in themselves for BTV replication but they also indicate the pathways that related viruses, which includes viruses that are pathogenic to man and animals, might also use providing an informed starting point for intervention or prevention. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Computational Breakthrough of Natural Lead Hits from the Genus of Arisaema against Human Respiratory Syncytial Virus.

    Science.gov (United States)

    Kant, Kamal; Lal, Uma Ranjan; Ghosh, Manik

    2018-01-01

    To date, efforts for the prevention and treatment of human respiratory syncytial virus (RSV) infection have been still vain, and there is no safe and effective clinical accepted vaccine. Arisaema genus has claimed for various traditional bioactivities, but scientific assessments are quite limited. This encouraged us to carry out our present study on around 60 phytoconstituents of different Arisaema species as a natural inhibitor against the human RSV. Selected 60 phytochemical entities were evaluated on the docking behavior of human RSV receptor (PDB: 4UCC) using Maestro 9.3 (Schrödinger, LLC, Cambridge, USA). Furthermore, kinetic properties and toxicity nature of top graded ligands were analyzed through QikProp and ProTox tools. Notably, rutin (glide score: -8.49), schaftoside (glide score: -8.18) and apigenin-6,8-di-C-β-D-galactoside (glide score - 7.29) have resulted in hopeful natural lead hits with an ideal range of kinetic descriptors values. ProTox tool (oral rodent toxicity) has resulted in likely toxicity targets of apex-graded tested ligands. Finally, the whole efforts can be explored further as a model to confirm its anti-human RSV potential with wet laboratory experiments. Rutin, schaftoside, and apigenin-6,8-di-C-β-D-galactoside showed promising top hits docking profile against human respiratory syncytial virusMoreover, absorption, distribution, metabolism, excretion properties (QikProp) of top hits resulted within an ideal range of kinetic descriptorsProTox tool highlighted toxicity class ranges, LD 50 values, and possible toxicity targets of apex-graded tested ligands. Abbreviations used: RSV: Respiratory syncytial virus, PRRSV: Porcine respiratory and reproductive syndrome virus, ADME-T: Absorption, distribution, metabolism, excretion, and toxicity.

  18. BOVINE RESPIRATORY SYNCYTIAL VIRUS EPIDEMIOLOGY AND RISK FACTORS ON CATTLE HERDS OF CAMPECHE STATE, MEXICO

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    Lisandro Alberto Encalada Mena

    2016-12-01

    Full Text Available High seroprevalence in Yucatan and proximity to the state of Campeche make it necessary to determine the seroprevalence and risk factors of bovine respiratory syncytial virus (VRSB in the state of Campeche, Mexico. Thus the objective of the present work was to determine the seroprevalence and risk factors bovine respiratory syncytial virus (BRSV of the state of Campeche, Mexico. The sampled of 36 cattle herds (842 sera were analyzed by indirect ELISA kit, in the 11 municipalities of Campeche. A survey to obtain risk factors (sex, age of animals, number of animals grazing density, management system, presence of sheep on the farm and access to the roadside was applied and calculated X2 for each variable considered. Of the total number of samples analyzed (842, 273 were positive (32.47%. The prevalence ranges found ranged from 0% to 84%, so in 9 of the herds there were no positive samples, indicating a 75% (27/36 of dispersion of this virus. X2 analysis indicated that all variables were significant and are risk factors regarding with respect to the variable seroprevalence of BRSV. The results indicate a wide circulation of BRSV and we suggest implement recommendations that will enable a lower spread of this virus in the cattle population.

  19. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool.

    Science.gov (United States)

    Mesquita, Flávio da Silva; Oliveira, Danielle Bruna Leal de; Crema, Daniela; Pinez, Célia Miranda Nunes; Colmanetti, Thaís Cristina; Thomazelli, Luciano Matsumia; Gilio, Alfredo Elias; Vieira, Sandra Elisabeth; Martinez, Marina Baquerizo; Botosso, Viviane Fongaro; Durigon, Edison Luiz

    The aim of this study was to evaluate the QuickVue ® RSV Test Kit (QUIDEL Corp, CA, USA) as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue ® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. From 313 positive samples by immunofluorescence assays, 282 (90%) were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue ® RSV Test and viral load or specific strain. The QuickVue ® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. This study demonstrated that the QuickVue ® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  20. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool,

    Directory of Open Access Journals (Sweden)

    Flávio da Silva Mesquita

    Full Text Available Abstract Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

  1. Role of Bibersteinia trehalosi, respiratory syncytial virus, and parainfluenza-3 virus in bighorn sheep pneumonia.

    Science.gov (United States)

    Dassanayake, Rohana P; Shanthalingam, Sudarvili; Subramaniam, Renuka; Herndon, Caroline N; Bavananthasivam, Jegarubee; Haldorson, Gary J; Foreyt, William J; Evermann, James F; Herrmann-Hoesing, Lynn M; Knowles, Donald P; Srikumaran, Subramaniam

    2013-02-22

    Pneumonic bighorn sheep (BHS) have been found to be culture- and/or sero-positive for Bibersteinia trehalosi, respiratory syncytial virus (RSV), and parainfluenza-3 virus (PI-3). The objective of this study was to determine whether these pathogens can cause fatal pneumonia in BHS. In the first study, two groups of four BHS each were intra-tracheally administered with leukotoxin-positive (Group I) or leukotoxin-negative (Group II) B. trehalosi. All four animals in Group I developed severe pneumonia, and two of them died within 3 days. The other two animals showed severe pneumonic lesions on euthanasia and necropsy. Animals in Group II neither died nor showed gross pneumonic lesions on necropsy, suggesting that leukotoxin-positive, but not leukotoxin-negative, B. trehalosi can cause fatal pneumonia in BHS. In the second study, two other groups of four BHS (Groups III and IV) were intra-nasally administered with a mixture of RSV and PI-3. Four days later, RSV/PI-3-inoculated Group IV and another group of four BHS (Group V, positive control) were intra-nasally administered with Mannheimia haemolytica, the pathogen that consistently causes fatal pneumonia in BHS. All four animals in group III developed pneumonia, but did not die during the study period. However all four animals in Group IV, and three animals in Group V developed severe pneumonia and died within two days of M. haemolytica inoculation. The fourth animal in Group V showed severe pneumonic lesions on euthanasia and necropsy. These findings suggest that RSV/PI-3 can cause non-fatal pneumonia, but are not necessary predisposing agents for M. haemolytica-caused pneumonia of BHS. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. A Case of Respiratory Syncytial Virus Infection in an HIV-Positive Adult

    Directory of Open Access Journals (Sweden)

    Aakriti Gupta

    2012-01-01

    Full Text Available Respiratory syncytial virus (RSV is commonly known to cause an influenza-like illness. However, it can also cause more severe disease in young children and older adults comprising of organ transplant patients with immunocompromised status. Till date, only four cases of RSV infections have been reported in HIV-positive adults. We describe here a case of HIV-positive female with relatively preserved immune function who presented with RSV infection requiring ventilation and showed improvement after prompt treatment with intravenous immunoglobulin.

  3. Human metapneumovirus and respiratory syncytial virus in hospitalized danish children with acute respiratory tract infection

    DEFF Research Database (Denmark)

    von Linstow, Marie-Louise; Henrik Larsen, Hans; Koch, Anders

    2004-01-01

    The newly discovered human metapneumovirus (hMPV) has been shown to be associated with respiratory illness. We determined the frequencies and clinical features of hMPV and respiratory syncytial virus (RSV) infections in 374 Danish children with 383 episodes of acute respiratory tract infection...... children 1-6 months of age. Asthmatic bronchitis was diagnosed in 66.7% of hMPV and 10.6% of RSV-infected children (p respiratory support. hMPV is present in young...

  4. Bovine respiratory syncytial virus (BRSV) pneumonia in beef calf herds despite vaccination

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Tegtmeier, C.; Pedersen, E.

    2001-01-01

    to the outbreak. The clinical signs comprised nasal discharge, pyrexia, cough and increased respiratory rates. A total of 28 calves died in the 2 herds. The laboratory investigations revealed that BRSV was involved and probably initiated both outbreaks. Furthermore, the serological results suggested...... beef herds failed to protect the calves against severe or even fatal BRSV mediated respiratory disease 2 months later.......The present report describes the clinical, pathological, serological and virological findings in calves from 2 larger Danish beef herds experiencing outbreaks of pneumonia. The calves had been vaccinated with an inactivated bovine respiratory syncytial virus (BRSV) vaccine 2 months prior...

  5. Prevention and treatment of respiratory syncytial virus bronchiolitis and postbronchiolitic wheezing

    Directory of Open Access Journals (Sweden)

    Kimpen Jan LL

    2002-06-01

    Full Text Available Abstract Respiratory syncytial virus (RSV is the primary cause of hospitalization for acute respiratory tract illness in general and specifically for bronchiolitis in young children. The link between RSV bronchiolitis and reactive airway disease is not completely understood, even though RSV bronchiolitis is frequently followed by recurrent episodes of wheezing. Therapy with ribavirin does not appear to significantly reduce long-term respiratory outcome of RSV lower respiratory tract infection, and corticosteroid or bronchodilator therapy may possibly improve outcomes only on a short-term basis. No vaccine against RSV is yet available. It is not known whether prophylaxis with RSV intravenous immune globulin or palivizumab can reduce postbronchiolitic wheezing.

  6. Excretion patterns of human metapneumovirus and respiratory syncytial virus among young children

    DEFF Research Database (Denmark)

    von Linstow, Marie-Louise; Eugen-Olsen, Jesper; Koch, A

    2006-01-01

    of the infected children showed to have an upper respiratory tract infection when following up. CONCLUSION: Viral RNA was present in nasal secretions, saliva, sweat, and faeces, but whether or not the virions were infectious and constitute a potential mode of transmission remains to be shown in future studies.......BACKGROUND: As respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) cause serious respiratory tract infections, the routes of transmission of these viruses are important to elucidate. We examined the modes of virus shedding and shedding duration of RSV and hMPV in young children....... METHODS: From each child in a group of 44 children (37 RSV-positive, 6 hMPV-positive, and 1 co-infected child), aged between 0.5-38 months, hospitalised at Hvidovre Hospital, Copenhagen, Denmark, one nasopharyngeal aspirate (NPA), saliva, urine, and faeces sample were collected at inclusion and weekly...

  7. Gene-gun DNA vaccination aggravates respiratory syncytial virus-induced pneumonitis

    DEFF Research Database (Denmark)

    Bartholdy, Christina; Olszewska, Wieslawa; Stryhn, Anette

    2004-01-01

    elicited with recombinant vaccinia virus expressing the complete RSV M2 protein, but stronger than those induced by a similar DNA construct without the beta2m gene. DNA vaccination led to enhanced pulmonary disease after RSV challenge, with increased weight loss and cell recruitment to the lung. Depletion......A CD8+ T-cell memory response to respiratory syncytial virus (RSV) was generated by using a DNA vaccine construct encoding the dominant Kd-restricted epitope from the viral transcription anti-terminator protein M2 (M2(82-90)), linked covalently to human beta2-microglobulin (beta2m). Cutaneous gene...... of CD8+ T cells reduced, but did not abolish, enhancement of disease. Mice vaccinated with a construct encoding a class I-restricted lymphocytic choriomeningitis virus epitope and beta2m suffered more severe weight loss after RSV infection than unvaccinated RSV-infected mice, although RSV-specific CD8...

  8. Simultaneous detection of respiratory syncytial virus types A and B ...

    African Journals Online (AJOL)

    ... A and B and influenza virus types A and B in community-acquired pneumonia by ... It is impossible to distinguish the cause of viral respiratory infections by their ... and pathogen-specific technique of multiplex RT-PCR in order to accomplish ...

  9. Respiratory syncytial virus fusion glycoprotein expressed in insect cells form protein nanoparticles that induce protective immunity in cotton rats.

    Directory of Open Access Journals (Sweden)

    Gale Smith

    Full Text Available Respiratory Syncytial Virus (RSV is an important viral agent causing severe respiratory tract disease in infants and children as well as in the elderly and immunocompromised individuals. The lack of a safe and effective RSV vaccine represents a major unmet medical need. RSV fusion (F surface glycoprotein was modified and cloned into a baculovirus vector for efficient expression in Sf9 insect cells. Recombinant RSV F was glycosylated and cleaved into covalently linked F2 and F1 polypeptides that formed homotrimers. RSV F extracted and purified from insect cell membranes assembled into 40 nm protein nanoparticles composed of multiple RSV F oligomers arranged in the form of rosettes. The immunogenicity and protective efficacy of purified RSV F nanoparticles was compared to live and formalin inactivated RSV in cotton rats. Immunized animals induced neutralizing serum antibodies, inhibited virus replication in the lungs, and had no signs of disease enhancement in the respiratory track of challenged animals. RSV F nanoparticles also induced IgG competitive for binding of palivizumab neutralizing monoclonal antibody to RSV F antigenic site II. Antibodies to this epitope are known to protect against RSV when passively administered in high risk infants. Together these data provide a rational for continued development a recombinant RSV F nanoparticle vaccine candidate.

  10. Non-specific Effect of Vaccines: Immediate Protection against Respiratory Syncytial Virus Infection by a Live Attenuated Influenza Vaccine

    Directory of Open Access Journals (Sweden)

    Young J. Lee

    2018-01-01

    Full Text Available The non-specific effects (NSEs of vaccines have been discussed for their potential long-term beneficial effects beyond direct protection against a specific pathogen. Cold-adapted, live attenuated influenza vaccine (CAIV induces local innate immune responses that provide a broad range of antiviral immunity. Herein, we examined whether X-31ca, a donor virus for CAIVs, provides non-specific cross-protection against respiratory syncytial virus (RSV. The degree of RSV replication was significantly reduced when X-31ca was administered before RSV infection without any RSV-specific antibody responses. The vaccination induced an immediate release of cytokines and infiltration of leukocytes into the respiratory tract, moderating the immune perturbation caused by RSV infection. The potency of protection against RSV challenge was significantly reduced in TLR3-/- TLR7-/- mice, confirming that the TLR3/7 signaling pathways are necessary for the observed immediate and short-term protection. The results suggest that CAIVs provide short-term, non-specific protection against genetically unrelated respiratory pathogens. The additional benefits of CAIVs in mitigating acute respiratory infections for which vaccines are not yet available need to be assessed in future studies.

  11. Cholesterol is required for stability and infectivity of influenza A and respiratory syncytial viruses.

    Science.gov (United States)

    Bajimaya, Shringkhala; Frankl, Tünde; Hayashi, Tsuyoshi; Takimoto, Toru

    2017-10-01

    Cholesterol-rich lipid raft microdomains in the plasma membrane are considered to play a major role in the enveloped virus lifecycle. However, the functional role of cholesterol in assembly, infectivity and stability of respiratory RNA viruses is not fully understood. We previously reported that depletion of cellular cholesterol by cholesterol-reducing agents decreased production of human parainfluenza virus type 1 (hPIV1) particles by inhibiting virus assembly. In this study, we analyzed the role of cholesterol on influenza A virus (IAV) and respiratory syncytial virus (RSV) production. Unlike hPIV1, treatment of human airway cells with the agents did not decrease virus particle production. However, the released virions were less homogeneous in density and unstable. Addition of exogenous cholesterol to the released virions restored virus stability and infectivity. Collectively, these data indicate a critical role of cholesterol in maintaining IAV and RSV membrane structure that is essential for sustaining viral stability and infectivity. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Functional organization of cytoplasmic inclusion bodies in cells infected by respiratory syncytial virus.

    Science.gov (United States)

    Rincheval, Vincent; Lelek, Mickael; Gault, Elyanne; Bouillier, Camille; Sitterlin, Delphine; Blouquit-Laye, Sabine; Galloux, Marie; Zimmer, Christophe; Eleouet, Jean-François; Rameix-Welti, Marie-Anne

    2017-09-15

    Infection of cells by respiratory syncytial virus induces the formation of cytoplasmic inclusion bodies (IBs) where all the components of the viral RNA polymerase complex are concentrated. However, the exact organization and function of these IBs remain unclear. In this study, we use conventional and super-resolution imaging to dissect the internal structure of IBs. We observe that newly synthetized viral mRNA and the viral transcription anti-terminator M2-1 concentrate in IB sub-compartments, which we term "IB-associated granules" (IBAGs). In contrast, viral genomic RNA, the nucleoprotein, the L polymerase and its cofactor P are excluded from IBAGs. Live imaging reveals that IBAGs are highly dynamic structures. Our data show that IBs are the main site of viral RNA synthesis. They further suggest that shortly after synthesis in IBs, viral mRNAs and M2-1 transiently concentrate in IBAGs before reaching the cytosol and suggest a novel post-transcriptional function for M2-1.Respiratory syncytial virus (RSV) induces formation of inclusion bodies (IBs) sheltering viral RNA synthesis. Here, Rincheval et al. identify highly dynamic IB-associated granules (IBAGs) that accumulate newly synthetized viral mRNA and the viral M2-1 protein but exclude viral genomic RNA and RNA polymerase complexes.

  13. Molecular Basis for the Selective Inhibition of Respiratory Syncytial Virus RNA Polymerase by 2'-Fluoro-4'-Chloromethyl-Cytidine Triphosphate.

    Directory of Open Access Journals (Sweden)

    Jerome Deval

    2015-06-01

    Full Text Available Respiratory syncytial virus (RSV causes severe lower respiratory tract infections, yet no vaccines or effective therapeutics are available. ALS-8176 is a first-in-class nucleoside analog prodrug effective in RSV-infected adult volunteers, and currently under evaluation in hospitalized infants. Here, we report the mechanism of inhibition and selectivity of ALS-8176 and its parent ALS-8112. ALS-8176 inhibited RSV replication in non-human primates, while ALS-8112 inhibited all strains of RSV in vitro and was specific for paramyxoviruses and rhabdoviruses. The antiviral effect of ALS-8112 was mediated by the intracellular formation of its 5'-triphosphate metabolite (ALS-8112-TP inhibiting the viral RNA polymerase. ALS-8112 selected for resistance-associated mutations within the region of the L gene of RSV encoding the RNA polymerase. In biochemical assays, ALS-8112-TP was efficiently recognized by the recombinant RSV polymerase complex, causing chain termination of RNA synthesis. ALS-8112-TP did not inhibit polymerases from host or viruses unrelated to RSV such as hepatitis C virus (HCV, whereas structurally related molecules displayed dual RSV/HCV inhibition. The combination of molecular modeling and enzymatic analysis showed that both the 2'F and the 4'ClCH2 groups contributed to the selectivity of ALS-8112-TP. The lack of antiviral effect of ALS-8112-TP against HCV polymerase was caused by Asn291 that is well-conserved within positive-strand RNA viruses. This represents the first comparative study employing recombinant RSV and HCV polymerases to define the selectivity of clinically relevant nucleotide analogs. Understanding nucleotide selectivity towards distant viral RNA polymerases could not only be used to repurpose existing drugs against new viral infections, but also to design novel molecules.

  14. The impact of laboratory characteristics on molecular detection of respiratory syncytial virus in a European multicentre quality control study

    NARCIS (Netherlands)

    Meerhoff, T. J.; MacKay, W. G.; Meijer, A.; Paget, W. J.; Niesters, H. G. M.; Kimpen, J. L. L.; Schellevis, F.

    2008-01-01

    The performance of nucleic acid amplification techniques for detecting respiratory syncytial virus (RSV) was evaluated in 25 laboratories across Europe by an external quality assessment study. In addition, factors related to the diagnostic performance of laboratories were explored. The results of

  15. Codetection of Respiratory Syncytial Virus in Habituated Wild Western Lowland Gorillas and Humans During a Respiratory Disease Outbreak

    Czech Academy of Sciences Publication Activity Database

    Grützmacher, K. S.; Köndgen, S.; Keil, V.; Todd, A.; Feistner, A.; Herbinger, I.; Petrželková, Klára Judita; Fuh, T.; Leendertz, S. A.; Calvignac-Spencer, S.; Leendertz, F. H.

    2016-01-01

    Roč. 13, č. 3 (2016), s. 499-510 ISSN 1612-9202 Institutional support: RVO:60077344 Keywords : respiratory disease * respiratory syncytial virus * enterovirus * western lowland gorillas * great apes * noninvasive detection Subject RIV: EE - Microbiology, Virology Impact factor: 2.252, year: 2016

  16. Codetection of respiratory syncytial virus in habituated wild western lowland gorillas and humans during a respiratory disease outbreak

    Czech Academy of Sciences Publication Activity Database

    Grützmacher, K. S.; Köndgen, S.; Keil, V.; Todd, A.; Feistner, A.; Herbinger, I.; Petrželková, Klára Judita; Fuh, T.; Leendertz, S. A.; Calvignac-Spencer, S.; Leendertz, F. H.

    2016-01-01

    Roč. 13, č. 3 (2016), s. 499-510 ISSN 1612-9202 Institutional support: RVO:68081766 Keywords : respiratory disease * respiratory syncytial virus * enterovirus * western lowland gorillas * great apes * noninvasive detection Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.252, year: 2016

  17. GENETIC SUSCEPTIBILITY TO RESPIRATORY SYNCYTIAL VIRUS BRONCHIOLITIS IN PRETERM CHILDREN IS ASSOCIATED WITH AIRWAY REMODELING GENES AND INNATE IMMUNE GENES

    NARCIS (Netherlands)

    Siezen, Christine L. E.; Bont, Louis; Hodemaekers, Hennie M.; Ermers, Marieke J.; Doornbos, Gerda; van't Slot, Ruben; Wijmenga, Ciska; van Hottwelingen, Hans C.; Kimpen, Jan L. L.; Kimman, Tjeerd G.; Hoebee, Barbara; Janssen, Riny

    Prematurity is a risk factor for severe respiratory syncytial virus bronchiolitis. We show that genetic factors in innate immune genes (IFNA13, IFNAR2, STAT2. IL27, NFKBIA, C3, IL1RN, TLR5), in innate and adaptive immunity (IFNG), and in airway remodeling genes (ADAM33 and TGFBR1), affect disease

  18. Defining the Risk and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Infants with Chronic Lung Disease

    NARCIS (Netherlands)

    Paes, Bosco; Fauroux, Brigitte; Figueras-Aloy, Josep; Bont, Louis; Checchia, Paul A; Simões, Eric A F; Manzoni, Paolo; Carbonell-Estrany, Xavier

    2016-01-01

    INTRODUCTION: The REGAL (RSV evidence-a geographical archive of the literature) series provide a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This third publication covers the risk and burden of RSV

  19. Prospective validation of a prognostic model for respiratory syncytial virus bronchiolitis in late preterm infants: a multicenter birth cohort study

    NARCIS (Netherlands)

    Blanken, M.O.; Koffijberg, H.; Nibbelke, E.E.; Rovers, M.M.; Bont, L.; Liem, K.D.; et al.,

    2013-01-01

    OBJECTIVES: This study aimed to update and validate a prediction rule for respiratory syncytial virus (RSV) hospitalization in preterm infants 33-35 weeks gestational age (WGA). STUDY DESIGN: The RISK study consisted of 2 multicenter prospective birth cohorts in 41 hospitals. Risk factors were

  20. The human cathelicidin LL-37 has antiviral activity against respiratory syncytial virus.

    Directory of Open Access Journals (Sweden)

    Silke M Currie

    Full Text Available Respiratory syncytial virus is a leading cause of lower respiratory tract illness among infants, the elderly and immunocompromised individuals. Currently, there is no effective vaccine or disease modifying treatment available and novel interventions are urgently required. Cathelicidins are cationic host defence peptides expressed in the inflamed lung, with key roles in innate host defence against infection. We demonstrate that the human cathelicidin LL-37 has effective antiviral activity against RSV in vitro, retained by a truncated central peptide fragment. LL-37 prevented virus-induced cell death in epithelial cultures, significantly inhibited the production of new infectious particles and diminished the spread of infection, with antiviral effects directed both against the viral particles and the epithelial cells. LL-37 may represent an important targetable component of innate host defence against RSV infection. Prophylactic modulation of LL-37 expression and/or use of synthetic analogues post-infection may represent future novel strategies against RSV infection.

  1. Respiratory syncytial virus infection facilitates acute colonization of Pseudomonas aeruginosa in mice

    DEFF Research Database (Denmark)

    de Vrankrijker, Angélica M M; Wolfs, Tom F W; Ciofu, Oana

    2009-01-01

    virus infections in facilitating colonization and infection with P. aeruginosa. A study was undertaken to determine whether respiratory syncytial virus (RSV) infection could facilitate the initiation of an acute infection with P. aeruginosa in vivo. Balb/c mice were infected intranasally with P......Pseudomonas aeruginosa causes opportunistic infections in immunocompromised individuals and patients ventilated mechanically and is the major pathogen in patients with cystic fibrosis, in which it causes chronic infections. Epidemiological, in vitro and animal data suggest a role for respiratory....... These results suggest that RSV can facilitate the initiation of acute P. aeruginosa infection without the RSV infection being clinically apparent. This could have implications for treatment strategies to prevent opportunistic P. aeruginosa lung infection....

  2. Virus-like particle vaccine primes immune responses preventing inactivated-virus vaccine-enhanced disease against respiratory syncytial virus.

    Science.gov (United States)

    Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Youri; Kwon, Young-Man; Kang, Sang-Moo

    2017-11-01

    Formalin inactivated respiratory syncytial virus (FI-RSV) vaccination caused vaccine-enhanced respiratory disease (ERD) upon exposure to RSV in children. Virus-like particles presenting RSV F fusion protein (F VLP) are known to increase T helper type-1 (Th1) immune responses and avoid ERD in animal models. We hypothesized that F VLP would prime immune responses preventing ERD upon subsequent exposure to ERD-prone FI-RSV. Here, we demonstrated that heterologous F VLP priming and FI-RSV boosting of mice prevented FI-RSV vaccine-enhanced lung inflammation and eosinophilia upon RSV challenge. F VLP priming redirected pulmonary T cells toward effector CD8 T cells producing Th1 cytokines and significantly suppressed pulmonary Th2 cytokines. This study suggests that RSV F VLP priming would modulate and shift immune responses to subsequent exposure to ERD-prone FI-RSV vaccine and RSV infection, suppressing Th2 immune-mediated pulmonary histopathology and eosinophilia. Copyright © 2017. Published by Elsevier Inc.

  3. Intranasal Administration of Maleic Anhydride-Modified Human Serum Albumin for Pre-Exposure Prophylaxis of Respiratory Syncytial Virus Infection

    Directory of Open Access Journals (Sweden)

    Zhiwu Sun

    2015-02-01

    Full Text Available Respiratory syncytial virus (RSV is the leading cause of pediatric viral respiratory tract infections. Neither vaccine nor effective antiviral therapy is available to prevent and treat RSV infection. Palivizumab, a humanized monoclonal antibody, is the only product approved to prevent serious RSV infection, but its high cost is prohibitive in low-income countries. Here, we aimed to identify an effective, safe, and affordable antiviral agent for pre-exposure prophylaxis (PrEP of RSV infection in children at high risk. We found that maleic anhydride (ML-modified human serum albumin (HSA, designated ML-HSA, exhibited potent antiviral activity against RSV and that the percentages of the modified lysines and arginies in ML- are correlated with such anti-RSV activity. ML-HSA inhibited RSV entry and replication by interacting with viral G protein and blocking RSV attachment to the target cells, while ML-HAS neither bound to F protein, nor inhibited F protein-mediated membrane fusion. Intranasal administration of ML-HSA before RSV infection resulted in significant decrease of the viral titers in the lungs of mice. ML-HSA shows promise for further development into an effective, safe, affordable, and easy-to-use intranasal regimen for pre-exposure prophylaxis of RSV infection in children at high risk in both low- and high-income countries.

  4. Combined virus-like particle and fusion protein-encoding DNA vaccination of cotton rats induces protection against respiratory syncytial virus without causing vaccine-enhanced disease

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Park, Soojin; Kwon, Young-Man; Lee, Youri; Ko, Eun-Ju; Jung, Yu-Jin [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Lee, Jong Seok [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); National Institute of Biological Resources, Incheon (Korea, Republic of); Kim, Yu-Jin [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Lee, Yu-Na; Kim, Min-Chul [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Animal and Plant Quarantine Agency, Gyeonggi-do, Gimcheon, Gyeongsangbukdo (Korea, Republic of); Cho, Minkyoung [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Kang, Sang-Moo, E-mail: skang24@gsu.edu [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States)

    2016-07-15

    A safe and effective vaccine against respiratory syncytial virus (RSV) should confer protection without causing vaccine-enhanced disease. Here, using a cotton rat model, we investigated the protective efficacy and safety of an RSV combination vaccine composed of F-encoding plasmid DNA and virus-like particles containing RSV fusion (F) and attachment (G) glycoproteins (FFG-VLP). Cotton rats with FFG-VLP vaccination controlled lung viral replication below the detection limit, and effectively induced neutralizing activity and antibody-secreting cell responses. In comparison with formalin inactivated RSV (FI-RSV) causing severe RSV disease after challenge, FFG-VLP vaccination did not cause weight loss, airway hyper-responsiveness, IL-4 cytokines, histopathology, and infiltrates of proinflammatory cells such as eosinophils. FFG-VLP was even more effective in preventing RSV-induced pulmonary inflammation than live RSV infections. This study provides evidence that FFG-VLP can be developed into a safe and effective RSV vaccine candidate. - Highlights: • Combined RSV FFG VLP vaccine is effective in inducing F specific responses. • FFG VLP vaccine confers RSV neutralizing activity and viral control in cotton rats. • Cotton rats with RSV FFG VLP vaccination do not show vaccine-enhanced disease. • Cotton rats with FFG VLP vaccine induce F specific antibody secreting cell responses. • Cotton rats with FFG VLP do not induce lung cellular infiltrates and Th2 cytokine.

  5. Combined virus-like particle and fusion protein-encoding DNA vaccination of cotton rats induces protection against respiratory syncytial virus without causing vaccine-enhanced disease

    International Nuclear Information System (INIS)

    Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Park, Soojin; Kwon, Young-Man; Lee, Youri; Ko, Eun-Ju; Jung, Yu-Jin; Lee, Jong Seok; Kim, Yu-Jin; Lee, Yu-Na; Kim, Min-Chul; Cho, Minkyoung; Kang, Sang-Moo

    2016-01-01

    A safe and effective vaccine against respiratory syncytial virus (RSV) should confer protection without causing vaccine-enhanced disease. Here, using a cotton rat model, we investigated the protective efficacy and safety of an RSV combination vaccine composed of F-encoding plasmid DNA and virus-like particles containing RSV fusion (F) and attachment (G) glycoproteins (FFG-VLP). Cotton rats with FFG-VLP vaccination controlled lung viral replication below the detection limit, and effectively induced neutralizing activity and antibody-secreting cell responses. In comparison with formalin inactivated RSV (FI-RSV) causing severe RSV disease after challenge, FFG-VLP vaccination did not cause weight loss, airway hyper-responsiveness, IL-4 cytokines, histopathology, and infiltrates of proinflammatory cells such as eosinophils. FFG-VLP was even more effective in preventing RSV-induced pulmonary inflammation than live RSV infections. This study provides evidence that FFG-VLP can be developed into a safe and effective RSV vaccine candidate. - Highlights: • Combined RSV FFG VLP vaccine is effective in inducing F specific responses. • FFG VLP vaccine confers RSV neutralizing activity and viral control in cotton rats. • Cotton rats with RSV FFG VLP vaccination do not show vaccine-enhanced disease. • Cotton rats with FFG VLP vaccine induce F specific antibody secreting cell responses. • Cotton rats with FFG VLP do not induce lung cellular infiltrates and Th2 cytokine.

  6. Long-Term Shedding of Influenza Virus, Parainfluenza Virus, Respiratory Syncytial Virus and Nosocomial Epidemiology in Patients with Hematological Disorders.

    Directory of Open Access Journals (Sweden)

    Nicola Lehners

    Full Text Available Respiratory viruses are a cause of upper respiratory tract infections (URTI, but can be associated with severe lower respiratory tract infections (LRTI in immunocompromised patients. The objective of this study was to investigate the genetic variability of influenza virus, parainfluenza virus and respiratory syncytial virus (RSV and the duration of viral shedding in hematological patients. Nasopharyngeal swabs from hematological patients were screened for influenza, parainfluenza and RSV on admission as well as on development of respiratory symptoms. Consecutive swabs were collected until viral clearance. Out of 672 tested patients, a total of 111 patients (17% were infected with one of the investigated viral agents: 40 with influenza, 13 with parainfluenza and 64 with RSV; six patients had influenza/RSV or parainfluenza/RSV co-infections. The majority of infected patients (n = 75/111 underwent stem cell transplantation (42 autologous, 48 allogeneic, 15 autologous and allogeneic. LRTI was observed in 48 patients, of whom 15 patients developed severe LRTI, and 13 patients with respiratory tract infection died. Phylogenetic analysis revealed a variety of influenza A(H1N1pdm09, A(H3N2, influenza B, parainfluenza 3 and RSV A, B viruses. RSV A was detected in 54 patients, RSV B in ten patients. The newly emerging RSV A genotype ON1 predominated in the study cohort and was found in 48 (75% of 64 RSV-infected patients. Furthermore, two distinct clusters were detected for RSV A genotype ON1, identical RSV G gene sequences in these patients are consistent with nosocomial transmission. Long-term viral shedding for more than 30 days was significantly associated with prior allogeneic transplantation (p = 0.01 and was most pronounced in patients with RSV infection (n = 16 with a median duration of viral shedding for 80 days (range 35-334 days. Long-term shedding of respiratory viruses might be a catalyzer of nosocomial transmission and must be considered for

  7. Curcumin modified silver nanoparticles for highly efficient inhibition of respiratory syncytial virus infection

    Science.gov (United States)

    Yang, Xiao Xi; Li, Chun Mei; Huang, Cheng Zhi

    2016-01-01

    Interactions between nanoparticles and viruses have attracted increasing attention due to the antiviral activity of nanoparticles and the resulting possibility to be employed as biomedical interventions. In this contribution, we developed a very simple route to prepare uniform and stable silver nanoparticles (AgNPs) with antiviral properties by using curcumin, which is a member of the ginger family isolated from rhizomes of the perennial herb Curcuma longa and has a wide range of biological activities like antioxidant, antifungal, antibacterial and anti-inflammatory effects, and acts as reducing and capping agents in this synthetic route. The tissue culture infectious dose (TCID50) assay showed that the curcumin modified silver nanoparticles (cAgNPs) have a highly efficient inhibition effect against respiratory syncytial virus (RSV) infection, giving a decrease of viral titers about two orders of magnitude at the concentration of cAgNPs under which no toxicity was found to the host cells. Mechanism investigations showed that cAgNPs could prevent RSV from infecting the host cells by inactivating the virus directly, indicating that cAgNPs are a novel promising efficient virucide for RSV.Interactions between nanoparticles and viruses have attracted increasing attention due to the antiviral activity of nanoparticles and the resulting possibility to be employed as biomedical interventions. In this contribution, we developed a very simple route to prepare uniform and stable silver nanoparticles (AgNPs) with antiviral properties by using curcumin, which is a member of the ginger family isolated from rhizomes of the perennial herb Curcuma longa and has a wide range of biological activities like antioxidant, antifungal, antibacterial and anti-inflammatory effects, and acts as reducing and capping agents in this synthetic route. The tissue culture infectious dose (TCID50) assay showed that the curcumin modified silver nanoparticles (cAgNPs) have a highly efficient inhibition

  8. Memory CD8 T cells mediate severe immunopathology following respiratory syncytial virus infection.

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    Megan E Schmidt

    2018-01-01

    Full Text Available Memory CD8 T cells can provide protection from re-infection by respiratory viruses such as influenza and SARS. However, the relative contribution of memory CD8 T cells in providing protection against respiratory syncytial virus (RSV infection is currently unclear. To address this knowledge gap, we utilized a prime-boost immunization approach to induce robust memory CD8 T cell responses in the absence of RSV-specific CD4 T cells and antibodies. Unexpectedly, RSV infection of mice with pre-existing CD8 T cell memory led to exacerbated weight loss, pulmonary disease, and lethal immunopathology. The exacerbated disease in immunized mice was not epitope-dependent and occurred despite a significant reduction in RSV viral titers. In addition, the lethal immunopathology was unique to the context of an RSV infection as mice were protected from a normally lethal challenge with a recombinant influenza virus expressing an RSV epitope. Memory CD8 T cells rapidly produced IFN-γ following RSV infection resulting in elevated protein levels in the lung and periphery. Neutralization of IFN-γ in the respiratory tract reduced morbidity and prevented mortality. These results demonstrate that in contrast to other respiratory viruses, RSV-specific memory CD8 T cells can induce lethal immunopathology despite mediating enhanced viral clearance.

  9. Severity of viral coinfection in hospitalized infants with respiratory syncytial virus infection.

    Science.gov (United States)

    De Paulis, Milena; Gilio, Alfredo Elias; Ferraro, Alexandre Archanjo; Ferronato, Angela Esposito; do Sacramento, Patrícia Rossi; Botosso, Viviane Fongaro; Oliveira, Danielle Bruna Leal de; Marinheiro, Juliana Cristina; Hársi, Charlotte Marianna; Durigon, Edison Luiz; Vieira, Sandra Elisabete

    2011-01-01

    To compare the severity of single respiratory syncytial virus (RSV) infections with that of coinfections. A historical cohort was studied, including hospitalized infants with acute RSV infection. Nasopharyngeal aspirate samples were collected from all patients to detect eight respiratory viruses using molecular biology techniques. The following outcomes were analyzed: duration of hospitalization and of oxygen therapy, intensive care unit admission and need of mechanical ventilation. Results were adjusted for confounding factors (prematurity, age and breastfeeding). A hundred and seventy six infants with bronchiolitis and/or pneumonia were included in the study. Their median age was 4.5 months. A hundred and twenty one had single RSV infection and 55 had coinfections (24 RSV + adenovirus, 16 RSV + human metapneumovirus and 15 other less frequent viral associations). The four severity outcomes under study were similar in the group with single RSV infection and in the coinfection groups, independently of what virus was associated with RSV. Virus coinfections do not seem to affect the prognosis of hospitalized infants with acute RSV infection.

  10. Immunological Features of Respiratory Syncytial Virus-Caused Pneumonia—Implications for Vaccine Design

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    Emma Rey-Jurado

    2017-03-01

    Full Text Available The human respiratory syncytial virus (hRSV is the causative agent for high rates of hospitalizations due to viral bronchiolitis and pneumonia worldwide. Such a disease is characterized by an infection of epithelial cells of the distal airways that leads to inflammation and subsequently to respiratory failure. Upon infection, different pattern recognition receptors recognize the virus and trigger the innate immune response against the hRSV. Further, T cell immunity plays an important role for virus clearance. Based on animal studies, it is thought that the host immune response to hRSV is based on a biased T helper (Th-2 and Th17 T cell responses with the recruitment of T cells, neutrophils and eosinophils to the lung, causing inflammation and tissue damage. In contrast, human immunity against RSV has been shown to be more complex with no definitive T cell polarization profile. Nowadays, only a humanized monoclonal antibody, known as palivizumab, is available to protect against hRSV infection in high-risk infants. However, such treatment involves several injections at a significantly high cost. For these reasons, intense research has been focused on finding novel vaccines or therapies to prevent hRSV infection in the population. Here, we comprehensively review the recent literature relative to the immunological features during hRSV infection, as well as the new insights into preventing the disease caused by this virus.

  11. Respiratory syncytial virus subunit vaccine based on a recombinant fusion protein expressed transiently in mammalian cells.

    Science.gov (United States)

    Nallet, Sophie; Amacker, Mario; Westerfeld, Nicole; Baldi, Lucia; König, Iwo; Hacker, David L; Zaborosch, Christiane; Zurbriggen, Rinaldo; Wurm, Florian M

    2009-10-30

    Although respiratory syncytial virus (RSV) causes severe lower respiratory tract infection in infants and adults at risk, no RSV vaccine is currently available. In this report, efforts toward the generation of an RSV subunit vaccine using recombinant RSV fusion protein (rRSV-F) are described. The recombinant protein was produced by transient gene expression (TGE) in suspension-adapted human embryonic kidney cells (HEK-293E) in 4 L orbitally shaken bioreactors. It was then purified and formulated in immunostimulating reconstituted influenza virosomes (IRIVs). The candidate vaccine induced anti-RSV-F neutralizing antibodies in mice, and challenge studies in cotton rats are ongoing. If successful in preclinical and clinical trials, this will be the first recombinant subunit vaccine produced by large-scale TGE in mammalian cells.

  12. Validation of a pediatric caregiver diary to measure symptoms of postacute respiratory syncytial virus bronchiolitis

    DEFF Research Database (Denmark)

    Santanello, Nancy C; Norquist, Josephine M; Nelsen, Linda M

    2005-01-01

    consistent, supporting a unidimensional scale structure. Test-retest reliabilities for the percentage of SFD and CSS were above the recommended cut point of 0.70. Cross-sectional and longitudinal correlations were sizeable and statistically significant, demonstrating construct validity. Hypothesized known......Acute respiratory syncytial virus (RSV)-induced bronchiolitis is often associated with continuing respiratory symptoms following hospitalization. To date, there is no validated objective measure to evaluate symptoms of RSV-induced bronchiolitis. We report on the reliability, validity...... the 4-week treatment period of the reported prospective, placebo-controlled trial of montelukast for treatment of postacute RSV were used to assess reliability (internal consistency and test-retest), construct validity (cross-sectional and longitudinal correlations), discriminant validity (known...

  13. Respiratory Syncytial Virus Pneumonia Treated with Lower-Dose Palivizumab in a Heart Transplant Recipient

    Directory of Open Access Journals (Sweden)

    J. L. Grodin

    2012-01-01

    Full Text Available Respiratory syncytial virus (RSV is an important community-acquired pathogen that can cause significant morbidity and mortality in patients who have compromised pulmonary function, are elderly, or are immunosuppressed. This paper describes a 70-year-old man with a remote history of heart transplantation who presented with signs and symptoms of pneumonia. Chest computed tomography (CT imaging demonstrated new patchy ground glass infiltrates throughout the upper and lower lobes of the left lung, and the RSV direct fluorescence antibody (DFA was positive. The patient received aerosolized ribavirin, one dose of intravenous immunoglobulin, and one dose of palivizumab. After two months of followup, the patient had improved infiltrates on chest CT, improved pulmonary function testing, and no evidence of graft rejection or dysfunction. There are few data on RSV infections in heart transplant patients, but this case highlights the importance of considering this potentially serious infection and introduces a novel method of treatment.

  14. The causal direction in the association between respiratory syncytial virus hospitalization and asthma

    DEFF Research Database (Denmark)

    Stensballe, Lone Graff; Simonsen, Jacob Brunbjerg; Thomsen, Simon Francis

    2009-01-01

    BACKGROUND: Earlier studies have reported an increased risk of asthma after respiratory syncytial virus (RSV) hospitalization. Other studies found that asthmatic disposition and propensity to wheeze increase the risk of RSV hospitalization. OBJECTIVE: The current study examined the causal direction......; and asthma is associated with a long-term increased susceptibility for severe RSV disease, suggesting a host factor being responsible for the severe response to RSV infection. This suggests that severe RSV infection and asthma may share a common genetic predisposition and/or environmental exposure....... was increased as much as 6-fold to 8-fold during the first 2 months after RSV hospitalization but was no longer increased 1 year later. Asthma increased the risk of RSV hospitalization by 3-fold, and the risk was not time-dependent. Analyzing these associations on the basis of asthma defined from use of inhaled...

  15. Human metapneumovirus and respiratory syncytial virus in hospitalized danish children with acute respiratory tract infection

    DEFF Research Database (Denmark)

    von Linstow, Marie-Louise; Larsen, Hans Henrik; Eugen-Olsen, Jesper

    2004-01-01

    The newly discovered human metapneumovirus (hMPV) has been shown to be associated with respiratory illness. We determined the frequencies and clinical features of hMPV and respiratory syncytial virus (RSV) infections in 374 Danish children with 383 episodes of acute respiratory tract infection...... children 1-6 months of age. Asthmatic bronchitis was diagnosed in 66.7% of hMPV and 10.6% of RSV-infected children (p infected children required respiratory support. hMPV is present in young.......6%) ARTI episodes by real-time reverse transcription-polymerase chain reaction using primers targeting the hMPV N gene and the RSV L gene. Two children were co-infected with hMPV and RSV. They were excluded from statistical analysis. Hospitalization for ARTI caused by hMPV was restricted to very young...

  16. The influence of diurnal temperature range on the incidence of respiratory syncytial virus in Japan.

    Science.gov (United States)

    Onozuka, D

    2015-03-01

    The incidence of respiratory syncytial virus (RSV) has been reported to exhibit seasonal variation. However, the impact of diurnal temperature range (DTR) on RSV has not been investigated. After acquiring data related to cases of RSV and weather parameters of DTR in Fukuoka, Japan, between 2006 and 2012, we used negative binomial generalized linear models and distributed lag nonlinear models to assess the possible relationship between DTR and RSV cases, adjusting for confounding factors. Our analysis revealed that the weekly number of RSV cases increased with a relative risk of 3·30 (95% confidence interval 1·65-6·60) for every 1°C increase in DTR. Our study provides quantitative evidence that the number of RSV cases increased significantly with increasing DTR. We suggest that preventive measures for limiting the spread of RSV should be considered during extended periods of high DTR.

  17. Establishing Correlates of Protection for Vaccine Development: Considerations for the Respiratory Syncytial Virus Vaccine Field.

    Science.gov (United States)

    Kulkarni, Prasad S; Hurwitz, Julia L; Simões, Eric A F; Piedra, Pedro A

    2018-03-01

    Correlates of protection (CoPs) can play a significant role in vaccine development by assisting the selection of vaccine candidates for clinical trials, supporting clinical trial design and implementation, and simplifying tests of vaccine modifications. Because of this important role in vaccine development, it is essential that CoPs be defined by well-designed immunogenicity and efficacy studies, with attention paid to benefits and limitations. The respiratory syncytial virus (RSV) field is unique in that a great deal of information about the humoral response is available from basic research and clinical studies. Polyclonal and monoclonal antibodies have been used routinely in the clinic to protect vulnerable infants from infection, providing a wealth of information about correlations between neutralizing antibodies and disease prevention. Considerations for the establishment of future CoPs to support RSV vaccine development in different populations are therefore discussed.

  18. Systemic signature of the lung response to respiratory syncytial virus infection.

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    Jeroen L A Pennings

    Full Text Available Respiratory Syncytial Virus is a frequent cause of severe bronchiolitis in children. To improve our understanding of systemic host responses to RSV, we compared BALB/c mouse gene expression responses at day 1, 2, and 5 during primary RSV infection in lung, bronchial lymph nodes, and blood. We identified a set of 53 interferon-associated and innate immunity genes that give correlated responses in all three murine tissues. Additionally, we identified blood gene signatures that are indicative of acute infection, secondary immune response, and vaccine-enhanced disease, respectively. Eosinophil-associated ribonucleases were characteristic for the vaccine-enhanced disease blood signature. These results indicate that it may be possible to distinguish protective and unfavorable patient lung responses via blood diagnostics.

  19. Autophagic machinery activated by dengue virus enhances virus replication

    International Nuclear Information System (INIS)

    Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

    2008-01-01

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication

  20. Respiratory syncytial virus infection enhances Pseudomonas aeruginosa biofilm growth through dysregulation of nutritional immunity.

    Science.gov (United States)

    Hendricks, Matthew R; Lashua, Lauren P; Fischer, Douglas K; Flitter, Becca A; Eichinger, Katherine M; Durbin, Joan E; Sarkar, Saumendra N; Coyne, Carolyn B; Empey, Kerry M; Bomberger, Jennifer M

    2016-02-09

    Clinical observations link respiratory virus infection and Pseudomonas aeruginosa colonization in chronic lung disease, including cystic fibrosis (CF) and chronic obstructive pulmonary disease. The development of P. aeruginosa into highly antibiotic-resistant biofilm communities promotes airway colonization and accounts for disease progression in patients. Although clinical studies show a strong correlation between CF patients' acquisition of chronic P. aeruginosa infections and respiratory virus infection, little is known about the mechanism by which chronic P. aeruginosa infections are initiated in the host. Using a coculture model to study the formation of bacterial biofilm formation associated with the airway epithelium, we show that respiratory viral infections and the induction of antiviral interferons promote robust secondary P. aeruginosa biofilm formation. We report that the induction of antiviral IFN signaling in response to respiratory syncytial virus (RSV) infection induces bacterial biofilm formation through a mechanism of dysregulated iron homeostasis of the airway epithelium. Moreover, increased apical release of the host iron-binding protein transferrin during RSV infection promotes P. aeruginosa biofilm development in vitro and in vivo. Thus, nutritional immunity pathways that are disrupted during respiratory viral infection create an environment that favors secondary bacterial infection and may provide previously unidentified targets to combat bacterial biofilm formation.

  1. Phosphorylation of human respiratory syncytial virus P protein at serine 54 regulates viral uncoating

    International Nuclear Information System (INIS)

    Asenjo, Ana; Gonzalez-Armas, Juan C.; Villanueva, Nieves

    2008-01-01

    The human respiratory syncytial virus (HRSV) structural P protein, phosphorylated at serine (S) and threonine (T) residues, is a co-factor of viral RNA polymerase. The phosphorylation of S54 is controlled by the coordinated action of two cellular enzymes: a lithium-sensitive kinase, probably glycogen synthetase kinase (GSK-3) β and protein phosphatase 2A (PP2A). Inhibition of lithium-sensitive kinase, soon after infection, blocks the viral growth cycle by inhibiting synthesis and/or accumulation of viral RNAs, proteins and extracellular particles. P protein phosphorylation at S54 is required to liberate viral ribonucleoproteins (RNPs) from M protein, during the uncoating process. Kinase inhibition, late in infection, produces a decrease in genomic RNA and infectious viral particles. LiCl, intranasally applied to mice infected with HRSV A2 strain, reduces the number of mice with virus in their lungs and the virus titre. Administration of LiCl to humans via aerosol should prevent HRSV infection, without secondary effects

  2. Nucleic acid-based vaccines targeting respiratory syncytial virus: Delivering the goods.

    Science.gov (United States)

    Smith, Trevor R F; Schultheis, Katherine; Broderick, Kate E

    2017-11-02

    Respiratory syncytial virus (RSV) is a massive medical burden on a global scale. Infants, children and the elderly represent the vulnerable populations. Currently there is no approved vaccine to protect against the disease. Vaccine development has been hindered by several factors including vaccine enhanced disease (VED) associated with formalin-inactivated RSV vaccines, inability of target populations to raise protective immune responses after vaccination or natural viral infection, and a lack of consensus concerning the most appropriate virus-associated target antigen. However, with recent advances in the molecular understanding of the virus, and design of highly characterized vaccines with enhanced immunogenicity there is new belief a RSV vaccine is possible. One promising approach is nucleic acid-based vaccinology. Both DNA and mRNA RSV vaccines are showing promising results in clinically relevant animal models, supporting their transition into humans. Here we will discuss this strategy to target RSV, and the ongoing studies to advance the nucleic acid vaccine platform as a viable option to protect vulnerable populations from this important disease.

  3. Ameliorating Effect of Dietary Xylitol on Human Respiratory Syncytial Virus (hRSV) Infection.

    Science.gov (United States)

    Xu, Mei Ling; Wi, Ga Ram; Kim, Hyoung Jin; Kim, Hong-Jin

    2016-01-01

    Human respiratory syncytial virus (hRSV) is the most common cause of bronchiolitis and pneumonia in infants. The lack of proper prophylactics and therapeutics for controlling hRSV infection has been of great concern worldwide. Xylitol is a well-known sugar substitute and its effect against bacteria in the oral cavity is well known. However, little is known of its effect on viral infections. In this study, the effect of dietary xylitol on hRSV infection was investigated in a mouse model for the first time. Mice received xylitol for 14 d prior to virus challenge and for a further 3 d post challenge. Significantly larger reductions in lung virus titers were observed in the mice receiving xylitol than in the controls receiving phosphate-buffered saline (PBS). In addition, fewer CD3(+) and CD3(+)CD8(+) lymphocytes, whose numbers reflect inflammatory status, were recruited in the mice receiving xylitol. These results indicate that dietary xylitol can ameliorate hRSV infections and reduce inflammation-associated immune responses to hRSV infection.

  4. Detection of an untyped strain of bovine respiratory syncytial virus in a dairy herd

    Directory of Open Access Journals (Sweden)

    Ingrid Bortolin Affonso

    2014-10-01

    Full Text Available Bovine respiratory syncytial virus (BRSV causes important lower respiratory tract illness in calves. According to F and G proteins genetic sequences, three BRSV subgroups have been reported and characterized in several countries, showing differences in its distribution. In Brazil, the virus is widely disseminated throughout the herds and the few characterized isolates revealed the solely occurrence of the subgroup B. This study describes the detection and characterization of an untyped BRSV strain from a twenty-days-old calf from a herd without clinical respiratory disease. Nasal swabs were analyzed by RT-nested PCR for the F and G proteins genes. One sample has amplified the F protein gene. Sequencing and subsequent phylogenetic reconstruction were accomplished, revealing that the strain could not be grouped with any other BRSV subgroups reported. This result may suggest that the BRSV is in constantly evolution, even in Brazil, where the vaccination is not a common practice. More detailed studies about BRSV characterization are necessary to know the virus subgroups distribution among the Brazilian herds to recommend appropriated immunoprophylaxis.

  5. Inhibition of Zika Virus Replication by Silvestrol

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    Fabian Elgner

    2018-03-01

    Full Text Available The Zika virus (ZIKV outbreak in 2016 in South America with specific pathogenic outcomes highlighted the need for new antiviral substances with broad-spectrum activities to react quickly to unexpected outbreaks of emerging viral pathogens. Very recently, the natural compound silvestrol isolated from the plant Aglaia foveolata was found to have very potent antiviral effects against the (−-strand RNA-virus Ebola virus as well as against Corona- and Picornaviruses with a (+-strand RNA-genome. This antiviral activity is based on the impaired translation of viral RNA by the inhibition of the DEAD-box RNA helicase eukaryotic initiation factor-4A (eIF4A which is required to unwind structured 5´-untranslated regions (5′-UTRs of several proto-oncogenes and thereby facilitate their translation. Zika virus is a flavivirus with a positive-stranded RNA-genome harboring a 5′-capped UTR with distinct secondary structure elements. Therefore, we investigated the effects of silvestrol on ZIKV replication in A549 cells and primary human hepatocytes. Two different ZIKV strains were used. In both infected A549 cells and primary human hepatocytes, silvestrol has the potential to exert a significant inhibition of ZIKV replication for both analyzed strains, even though the ancestor strain from Uganda is less sensitive to silvestrol. Our data might contribute to identify host factors involved in the control of ZIKV infection and help to develop antiviral concepts that can be used to treat a variety of viral infections without the risk of resistances because a host protein is targeted.

  6. Molecular epidemiology of the SH (small hydrophobic) gene of human respiratory syncytial virus (HRSV), over 2 consecutive years.

    Science.gov (United States)

    Lima, Hildenêr Nogueira; Botosso, Viviane Fongaro; Oliveira, Danielle Bruna Leal; Campos, Angélica Cristine de Almeida; Leal, Andrea Lima; Silva, Tereza Souza; Bosso, Patrícia Alves Ramos; Moraes, Claudia Trigo Pedroso; Filho, Claudionor Gomes da Silva; Vieira, Sandra Elisabete; Gilio, Alfredo Elias; Stewien, Klaus Eberhard; Durigon, Edison Luiz

    2012-01-01

    Human respiratory syncytial virus (HRSV) strains were isolated from nasopharyngeal aspirates collected from 965 children between 2004 and 2005, yielding 424 positive samples. We sequenced the small hydrophobic protein (SH) gene of 117 strains and compared them with other viruses identified worldwide. Phylogenetic analysis showed a low genetic variability among the isolates but allowed us to classify the viruses into different genotypes for both groups, HRSVA and HRSVB. It is also shown that the novel BA-like genotype was well segregated from the others, indicating that the mutations are not limited to the G gene. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Functional Impairment of Mononuclear Phagocyte System by the Human Respiratory Syncytial Virus

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    Karen Bohmwald

    2017-11-01

    Full Text Available The mononuclear phagocyte system (MPS comprises of monocytes, macrophages (MΦ, and dendritic cells (DCs. MPS is part of the first line of immune defense against a wide range of pathogens, including viruses, such as the human respiratory syncytial virus (hRSV. The hRSV is an enveloped virus that belongs to the Pneumoviridae family, Orthopneumovirus genus. This virus is the main etiological agent causing severe acute lower respiratory tract infection, especially in infants, children and the elderly. Human RSV can cause bronchiolitis and pneumonia and it has also been implicated in the development of recurrent wheezing and asthma. Monocytes, MΦ, and DCs significantly contribute to acute inflammation during hRSV-induced bronchiolitis and asthma exacerbation. Furthermore, these cells seem to be an important component for the association between hRSV and reactive airway disease. After hRSV infection, the first cells encountered by the virus are respiratory epithelial cells, alveolar macrophages (AMs, DCs, and monocytes in the airways. Because AMs constitute the predominant cell population at the alveolar space in healthy subjects, these cells work as major innate sentinels for the recognition of pathogens. Although adaptive immunity is crucial for viral clearance, AMs are required for the early immune response against hRSV, promoting viral clearance and controlling immunopathology. Furthermore, exposure to hRSV may affect the phagocytic and microbicidal capacity of monocytes and MΦs against other infectious agents. Finally, different studies have addressed the roles of different DC subsets during infection by hRSV. In this review article, we discuss the role of the lung MPS during hRSV infection and their involvement in the development of bronchiolitis.

  8. [Quantitative fluorogenic real-time PCR assay for respiratory syncytial virus detection].

    Science.gov (United States)

    Zhang, Qi-wei; You, Shang-you; Sun, Ji-min; Wu, Qi; Yu, Chun-hua; Zhang, Chu-yu

    2005-07-01

    To Establish a rapid and objective quantitative fluorogenic real-time PCR assay for early detection of human respiratory syncytial virus (hRSV). Two pairs of primers and one TaqMan Fluorogenic probe that are specific for the recognition of the most conservative N gene of hRSV for virus detection with LighCycler PCR in 93 nasopharyngeal secretion specimens collected from infants and young children. The assay was compared with virus isolation, routine PCR, nested PCR, and enzyme-linked immunosorbent assay (ELISA). This TaqMan assay had a sensitivity of 1 x 10(2) cDNA copies/microl with a dynamic range between 1 x 10(2) and 1 x 10(7) cDNA copies/microl, which was the same as that of nested PCR, but 10 times more sensitive than routine PCR. The specificity of the assay was evaluated by comparing hRSV with polivirus type 1, coxsackie virus type 2, influenza A, influenza B and adenovirus type 7. A PCR product of the expected size (195 bp) was produced and fluorescence signal detected for hRSV, but not for any of the other viruses. The results in LightCycler and Rotor-Gene instrument were consistent. Forty-four specimens (43.9%) were hRSV-positive with this assay and 4 (4/93,4.3%) were hRSV-positive with ELISA, showing rather low correlation between the two methods. No visible relation was found between the concentration of hRSV RNA and severity of the disease. This assay is rapid, sensitive, specific and quantitative, and has the potential of wide application for early diagnosis of hRSV infection and evaluation of the therapeutic effect.

  9. Evidence that the respiratory syncytial virus polymerase complex associates with lipid rafts in virus-infected cells: a proteomic analysis

    International Nuclear Information System (INIS)

    McDonald, Terence P.; Pitt, Andrew R.; Brown, Gaie; Rixon, Helen W. McL.; Sugrue, Richard J.

    2004-01-01

    The interaction between the respiratory syncytial virus (RSV) polymerase complex and lipid rafts was examined in HEp2 cells. Lipid-raft membranes were prepared from virus-infected cells and their protein content was analysed by Western blotting and mass spectrometry. This analysis revealed the presence of the N, P, L, M2-1 and M proteins. However, these proteins appeared to differ from one another in their association with these structures, with the M2-1 protein showing a greater partitioning into raft membranes compared to that of the N, P or M proteins. Determination of the polymerase activity profile of the gradient fractions revealed that 95% of the detectable viral enzyme activity was associated with lipid-raft membranes. Furthermore, analysis of virus-infected cells by confocal microscopy suggested an association between these proteins and the raft-lipid, GM1. Together, these results provide evidence that the RSV polymerase complex is able to associate with lipid rafts in virus-infected cells

  10. A single intranasal administration of virus-like particle vaccine induces an efficient protection for mice against human respiratory syncytial virus.

    Science.gov (United States)

    Jiao, Yue-Ying; Fu, Yuan-Hui; Yan, Yi-Fei; Hua, Ying; Ma, Yao; Zhang, Xiu-Juan; Song, Jing-Dong; Peng, Xiang-Lei; Huang, Jiaqiang; Hong, Tao; He, Jin-Sheng

    2017-08-01

    Human respiratory syncytial virus (RSV) is an important pediatric pathogen causing acute viral respiratory disease in infants and young children. However, no licensed vaccines are currently available. Virus-like particles (VLPs) may bring new hope to producing RSV VLP vaccine with high immunogenicity and safety. Here, we constructed the recombinants of matrix protein (M) and fusion glycoprotein (F) of RSV, respectively into a replication-deficient first-generation adenoviral vector (FGAd), which were used to co-infect Vero cells to assemble RSV VLPs successfully. The resulting VLPs showed similar immunoreactivity and function to RSV virion in vitro. Moreover, Th1 polarized response, and effective mucosal virus-neutralizing antibody and CD8 + T-cell responses were induced by a single intranasal (i.n.) administration of RSV VLPs rather than intramuscular (i.m.) inoculation, although the comparable RSV F-specific serum IgG and long-lasting RSV-specific neutralizing antibody were detected in the mice immunized by both routes. Upon RSV challenge, VLP-immunized mice showed increased viral clearance but decreased signs of enhanced lung pathology and fewer eosinophils compared to mice immunized with formalin-inactivated RSV (FI-RSV). In addition, a single i.n. RSV VLP vaccine has the capability to induce RSV-specific long-lasting neutralizing antibody responses observable up to 15 months. Our results demonstrate that the long-term and memory immune responses in mice against RSV were induced by a single i.n. administration of RSV VLP vaccine, suggesting a successful approach of RSV VLPs as an effective and safe mucosal vaccine against RSV infection, and an applicable and qualified platform of FGAd-infected Vero cells for VLP production. Copyright © 2017. Published by Elsevier B.V.

  11. The respiratory syncytial virus polymerase has multiple RNA synthesis activities at the promoter.

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    Sarah L Noton

    Full Text Available Respiratory syncytial virus (RSV is an RNA virus in the Family Paramyxoviridae. Here, the activities performed by the RSV polymerase when it encounters the viral antigenomic promoter were examined. RSV RNA synthesis was reconstituted in vitro using recombinant, isolated polymerase and an RNA oligonucleotide template representing nucleotides 1-25 of the trailer complement (TrC promoter. The RSV polymerase was found to have two RNA synthesis activities, initiating RNA synthesis from the +3 site on the promoter, and adding a specific sequence of nucleotides to the 3' end of the TrC RNA using a back-priming mechanism. Examination of viral RNA isolated from RSV infected cells identified RNAs initiated at the +3 site on the TrC promoter, in addition to the expected +1 site, and showed that a significant proportion of antigenome RNAs contained specific nucleotide additions at the 3' end, demonstrating that the observations made in vitro reflected events that occur during RSV infection. Analysis of the impact of the 3' terminal extension on promoter activity indicated that it can inhibit RNA synthesis initiation. These findings indicate that RSV polymerase-promoter interactions are more complex than previously thought and suggest that there might be sophisticated mechanisms for regulating promoter activity during infection.

  12. Down syndrome as risk factor for respiratory syncytial virus hospitalization: A prospective multicenter epidemiological study.

    Science.gov (United States)

    Sánchez-Luna, Manuel; Medrano, Constancio; Lirio, Julián

    2017-03-01

    Respiratory syncytial virus (RSV) infection in childhood, particularly in premature infants, is associated with significant morbidity and mortality. To compare the hospitalization rates due to RSV infection and severity of disease between infants with and without Down syndrome (DS) born at term and without other associated risk factors for severe RSV infection. In a prospective multicentre epidemiological study, 93 infants were included in the DS cohort and 68 matched by sex and data of birth (±1 week) and were followed up to 1 year of age and during a complete RSV season. The hospitalization rate for all acute respiratory infection was significantly higher in the DS cohort than in the non-DS cohort (44.1% vs 7.7%, P<.0001). Hospitalizations due to RSV were significantly more frequent in the DH cohort than in the non-DS cohort (9.7% vs 1.5%, P=.03). RSV prophylaxis was recorded in 33 (35.5%) infants with DS. The rate of hospitalization according to presence or absence of RSV immunoprophylaxis was 3.0% vs 15%, respectively. Infants with DS showed a higher rate of hospitalization due to acute lower respiratory tract infection and RSV infection compared to non-DS infants. Including DS infants in recommendations for immunoprophylaxis of RSV disease should be considered. © 2016 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  13. Respiratory Syncytial Virus (RSV RNA loads in peripheral blood correlates with disease severity in mice

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    Torres Juan

    2010-09-01

    Full Text Available Abstract Background Respiratory Syncytial Virus (RSV infection is usually restricted to the respiratory epithelium. Few studies have documented the presence of RSV in the systemic circulation, however there is no consistent information whether virus detection in the blood correlates with disease severity. Methods Balb/c mice were inoculated with live RSV, heat-inactivated RSV or medium. A subset of RSV-infected mice was treated with anti-RSV antibody 72 h post-inoculation. RSV RNA loads were measured by PCR in peripheral blood from day 1-21 post-inoculation and were correlated with upper and lower respiratory tract viral loads, the systemic cytokine response, lung inflammation and pulmonary function. Immunohistochemical staining was used to define the localization of RSV antigens in the respiratory tract and peripheral blood. Results RSV RNA loads were detected in peripheral blood from day 1 to 14 post-inoculation, peaked on day 5 and significantly correlated with nasal and lung RSV loads, airway obstruction, and blood CCL2 and CXCL1 expression. Treatment with anti-RSV antibody reduced blood RSV RNA loads and improved airway obstruction. Immunostaining identified RSV antigens in alveolar macrophages and peripheral blood monocytes. Conclusions RSV RNA was detected in peripheral blood upon infection with live RSV, followed a time-course parallel to viral loads assessed in the respiratory tract and was significantly correlated with RSV-induced airway disease.

  14. Recombinant Human Respiratory Syncytial Virus (RSV) Monoclonal Antibody Fab is Effective Therapeutically when Introduced Directly into the Lungs of RSV-Infected Mice

    Science.gov (United States)

    Crowe, James E., Jr.; Murphy, Brian R.; Chanock, Robert M.; Williamson, R. Anthony; Barbas, Carlos F., III; Burton, Dennis R.

    1994-02-01

    Previously, recombinant human respiratory syncytial virus (RSV) monoclonal antibody Fabs were generated by antigen selection from random combinatorial libraries displayed at the tip of filamentous phage. Two such Fabs, which exhibited high binding affinity for RSV F glycoprotein (a major protective antigen), were evaluated for therapeutic efficacy in infected mice just before or at the time of peak virus replication in the lungs. Fab 19, which neutralized RSV infectivity with high efficiency in tissue culture, was effective therapeutically when delivered directly into the lungs by intranasal instillation under anesthesia. In contrast, RSV Fab 126, which failed to neutralize virus in cell culture, did not exhibit a therapeutic effect under these conditions. The amount of Fab 19 required to effect a 5000- to 12,000-fold reduction in titer of RSV in the lungs within 24 hr was rather small. In four separate experiments, a single instillation of 12.9-50 μg of RSV Fab 19 was sufficient to achieve such a reduction in pulmonary virus in a 25g mouse. The use of Fabs instead of the whole immunoglobulin molecules from which they are derived reduced the protein content of a therapeutic dose. This is important because the protein load that can be delivered effectively into the lungs is limited. The therapeutic effect of a single treatment with Fab 19 was not sustained, so that a rebound in pulmonary virus titer occurred on the 2nd day after treatment. This rebound in pulmonary RSV titer could be prevented by treating infected mice with a single dose of Fab 19 daily for 3 days. These observations suggest that human monoclonal Fabs grown in Escherichia coli may prove useful in the treatment of serious RSV disease as well as diseases caused by other viruses where replication in vivo is limited primarily to the lumenal lining of the respiratory tract.

  15. Cyclophilin B facilitates the replication of Orf virus

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    Zhao, Kui; Li, Jida; He, Wenqi; Song, Deguang; Zhang, Ximu; Zhang, Di; Zhou, Yanlong; Gao, Feng

    2017-01-01

    Background Viruses interact with host cellular factors to construct a more favourable environment for their efficient replication. Expression of cyclophilin B (CypB), a cellular peptidyl-prolyl cis-trans isomerase (PPIase), was found to be significantly up-regulated. Recently, a number of studies have shown that CypB is important in the replication of several viruses, including Japanese encephalitis virus (JEV), hepatitis C virus (HCV) and human papillomavirus type 16 (HPV 16). However, the f...

  16. Respiratory Syncytial Virus-Infected Mesenchymal Stem Cells Regulate Immunity via Interferon Beta and Indoleamine-2,3-Dioxygenase.

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    Michael B Cheung

    Full Text Available Respiratory syncytial virus (RSV has been reported to infect human mesenchymal stem cells (MSCs but the consequences are poorly understood. MSCs are present in nearly every organ including the nasal mucosa and the lung and play a role in regulating immune responses and mediating tissue repair. We sought to determine whether RSV infection of MSCs enhances their immune regulatory functions and contributes to RSV-associated lung disease. RSV was shown to replicate in human MSCs by fluorescence microscopy, plaque assay, and expression of RSV transcripts. RSV-infected MSCs showed differentially altered expression of cytokines and chemokines such as IL-1β, IL6, IL-8 and SDF-1 compared to epithelial cells. Notably, RSV-infected MSCs exhibited significantly increased expression of IFN-β (~100-fold and indoleamine-2,3-dioxygenase (IDO (~70-fold than in mock-infected MSCs. IDO was identified in cytosolic protein of infected cells by Western blots and enzymatic activity was detected by tryptophan catabolism assay. Treatment of PBMCs with culture supernatants from RSV-infected MSCs reduced their proliferation in a dose dependent manner. This effect on PBMC activation was reversed by treatment of MSCs with the IDO inhibitors 1-methyltryptophan and vitamin K3 during RSV infection, a result we confirmed by CRISPR/Cas9-mediated knockout of IDO in MSCs. Neutralizing IFN-β prevented IDO expression and activity. Treatment of MSCs with an endosomal TLR inhibitor, as well as a specific inhibitor of the TLR3/dsRNA complex, prevented IFN-β and IDO expression. Together, these results suggest that RSV infection of MSCs alters their immune regulatory function by upregulating IFN-β and IDO, affecting immune cell proliferation, which may account for the lack of protective RSV immunity and for chronicity of RSV-associated lung diseases such as asthma and COPD.

  17. Profilin is required for viral morphogenesis, syncytium formation, and cell-specific stress fiber induction by respiratory syncytial virus

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    Barik Sailen

    2003-05-01

    Full Text Available Abstract Background Actin is required for the gene expression and morphogenesis of respiratory syncytial virus (RSV, a clinically important Pneumovirus of the Paramyxoviridae family. In HEp-2 cells, RSV infection also induces actin stress fibers, which may be important in the immunopathology of the RSV disease. Profilin, a major regulator of actin polymerization, stimulates viral transcription in vitro. Thus, we tested the role of profilin in RSV growth and RSV-actin interactions in cultured cells (ex vivo. Results We tested three cell lines: HEp-2 (human, A549 (human, and L2 (rat. In all three, RSV grew well and produced fused cells (syncytium, and two RSV proteins, namely, the phosphoprotein P and the nucleocapsid protein N, associated with profilin. In contrast, induction of actin stress fibers by RSV occurred in HEp-2 and L2 cells, but not in A549. Knockdown of profilin by RNA interference had a small effect on viral macromolecule synthesis but strongly inhibited maturation of progeny virions, cell fusion, and induction of stress fibers. Conclusions Profilin plays a cardinal role in RSV-mediated cell fusion and viral maturation. In contrast, interaction of profilin with the viral transcriptional proteins P and N may only nominally activate viral RNA-dependent RNA polymerase. Stress fiber formation is a cell-specific response to infection, requiring profilin and perhaps other signaling molecules that are absent in certain cell lines. Stress fibers per se play no role in RSV replication in cell culture. Clearly, the cellular architecture controls multiple steps of host-RSV interaction, some of which are regulated by profilin.

  18. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool

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    Flávio da Silva Mesquita

    2017-05-01

    Full Text Available Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Resumo: Objetivo: Avaliar o teste QuickVue® RSV Test Kit (QUIDEL Corp, CA, EUA para o diagn

  19. Analysis of the interaction between respiratory syncytial virus and lipid-rafts in Hep2 cells during infection

    International Nuclear Information System (INIS)

    Brown, Gaie; Jeffree, Chris E.; McDonald, Terence; McL Rixon, Helen W.; Aitken, James D.; Sugrue, Richard J.

    2004-01-01

    The assembly of respiratory syncytial virus (RSV) in lipid-rafts was examined in Hep2 cells. Confocal and electron microscopy showed that during RSV assembly, the cellular distribution of the complement regulatory proteins, decay accelerating factor (CD55) and CD59, changes and high levels of these cellular proteins are incorporated into mature virus filaments. The detergent-solubility properties of CD55, CD59, and the RSV fusion (F) protein were found to be consistent with each protein being located predominantly within lipid-raft structures. The levels of these proteins in cell-released virus were examined by immunoelectronmicroscopy and found to account for between 5% and 15% of the virus attachment (G) glycoprotein levels. Collectively, our findings suggest that an intimate association exists between RSV and lipid-raft membranes and that significant levels of these host-derived raft proteins, such as those regulating complement activation, are subsequently incorporated into the envelope of mature virus particles

  20. ACUTE RESPIRATORY SYNCYTIAL VIRUS INFECTION IN CHILDREN IN THE AGE ASPECT

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    V. B. Rovny

    2013-01-01

    Full Text Available The clinical features of laboratory-confirmed acute respiratory syncytial virus infection (ARSVI are described in 221 children of the age from 1 month to 5 years. Febrile fever has been recorded in 76% of patients with ARSVI, and significantly more often in children in the second year of life (92%, but the difference in the temerature or duration has not been found. 98% of children have had symptoms of the lower respiratory tract lesions. The most common ARSVI manifestations in the patients of the first year of life were obstructive diseases of the lower respiratory tract (obstructive bronchitis in 53% and bronchiolitis in 11% of children, in the patients of the second year of life — pneumonia (28%, p < 0,05 and catarrhal otitis (26%; p < 0,05. Bronchial obstruction syndrome in children of the first year of life was characterized by the significantly higher frequency (73% and the maximal duration (9,7 ± 1,08 days. The largest number of cases of the severe respiratory failure has been recorded among patients of the second year of life (3 degree of respiratory failure in 22% of patients, p < 0,05.

  1. Respiratory Syncytial Virus Disease Is Mediated by Age-Variable IL-33.

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    Jordy Saravia

    2015-10-01

    Full Text Available Respiratory syncytial virus (RSV is the most common cause of infant hospitalizations and severe RSV infections are a significant risk factor for childhood asthma. The pathogenic mechanisms responsible for RSV induced immunopathophysiology remain elusive. Using an age-appropriate mouse model of RSV, we show that IL-33 plays a critical role in the immunopathogenesis of severe RSV, which is associated with higher group 2 innate lymphoid cells (ILC2s specifically in neonates. Infection with RSV induced rapid IL-33 expression and an increase in ILC2 numbers in the lungs of neonatal mice; this was not observed in adult mice. Blocking IL-33 with antibodies or using an IL-33 receptor knockout mouse during infection was sufficient to inhibit RSV immunopathogenesis (i.e., airway hyperresponsiveness, Th2 inflammation, eosinophilia, and mucus hyperproduction; whereas administration of IL-33 to adult mice during RSV infection was sufficient to induce RSV disease. Additionally, elevated IL-33 and IL-13 were observed in nasal aspirates from infants hospitalized with RSV; these cytokines declined during convalescence. In summary, IL-33 is necessary, either directly or indirectly, to induce ILC2s and the Th2 biased immunopathophysiology observed following neonatal RSV infection. This study provides a mechanism involving IL-33 and ILC2s in RSV mediated human asthma.

  2. Transmission of Human Respiratory Syncytial Virus in the Immunocompromised Ferret Model

    Science.gov (United States)

    de Waal, Leon; Smits, Saskia L.; Veldhuis Kroeze, Edwin J. B.; van Amerongen, Geert; Pohl, Marie O.; Osterhaus, Albert D. M. E.; Stittelaar, Koert J.

    2018-01-01

    Human respiratory syncytial virus (HRSV) causes substantial morbidity and mortality in vulnerable patients, such as the very young, the elderly, and immunocompromised individuals of any age. Nosocomial transmission of HRSV remains a serious challenge in hospital settings, with intervention strategies largely limited to infection control measures, including isolation of cases, high standards of hand hygiene, cohort nursing, and use of personal protective equipment. No vaccines against HRSV are currently available, and treatment options are largely supportive care and expensive monoclonal antibody or antiviral therapy. The limitations of current animal models for HRSV infection impede the development of new preventive and therapeutic agents, and the assessment of their potential for limiting HRSV transmission, in particular in nosocomial settings. Here, we demonstrate the efficient transmission of HRSV from immunocompromised ferrets to both immunocompromised and immunocompetent contact ferrets, with pathological findings reproducing HRSV pathology in humans. The immunocompromised ferret-HRSV model represents a novel tool for the evaluation of intervention strategies against nosocomial transmission of HRSV. PMID:29301313

  3. Comparative epidemiology of human metapneumovirus- and respiratory syncytial virus-associated hospitalizations in Guatemala

    Science.gov (United States)

    McCracken, John P; Arvelo, Wences; Ortíz, José; Reyes, Lissette; Gray, Jennifer; Estevez, Alejandra; Castañeda, Oscar; Langley, Gayle; Lindblade, Kim A

    2014-01-01

    Background Human metapneumovirus (HMPV) is an important cause of acute respiratory infections (ARI), but little is known about how it compares with respiratory syncytial virus (RSV) in Central America. Objectives In this study, we describe hospitalized cases of HMPV- and RSV-ARI in Guatemala. Methods We conducted surveillance at three hospitals (November 2007–December 2012) and tested nasopharyngeal and oropharyngeal swab specimens for HMPV and RSV using real-time reverse transcription-polymerase chain reaction. We calculated incidence rates, and compared the epidemiology and outcomes of HMPV-positive versus RSV-positive and RSV-HMPV-negative cases. Results We enrolled and tested specimens from 6288 ARI cases; 596 (9%) were HMPV-positive and 1485 (24%) were RSV-positive. We observed a seasonal pattern of RSV but not HMPV. The proportion HMPV-positive was low (3%) and RSV-positive high (41%) for age Guatemala, but HMPV hospitalizations are less frequent than RSV and, in young children, less severe than other etiologies. Preventive interventions should take into account the wide variation in incidence by age and unpredictable timing of incidence peaks. PMID:24761765

  4. Interaction between human BAP31 and respiratory syncytial virus small hydrophobic (SH) protein

    International Nuclear Information System (INIS)

    Li, Yan; Jain, Neeraj; Limpanawat, Suweeraya; To, Janet; Quistgaard, Esben M.; Nordlund, Par; Thanabalu, Thirumaran; Torres, Jaume

    2015-01-01

    The small hydrophobic (SH) protein is a short channel-forming polypeptide encoded by the human respiratory syncytial virus (hRSV). Deletion of SH protein leads to the viral attenuation in mice and primates, and delayed apoptosis in infected cells. We have used a membrane-based yeast two-hybrid system (MbY2H) and a library from human lung cDNA to detect proteins that bind SH protein. This led to the identification of a membrane protein, B-cell associated protein 31 (BAP31). Transfected SH protein co-localizes with transfected BAP31 in cells, and pulls down endogenous BAP31. Titration of purified C-terminal endodomain of BAP31 against isotopically labeled SH protein in detergent micelles suggests direct interaction between the two proteins. Given the key role of BAP31 in protein trafficking and its critical involvement in pro- and anti-apoptotic pathways, this novel interaction may constitute a potential drug target. - Highlights: • A yeast two-hybrid system (MbY2H) detected BAP31 as a binder of RSV SH protein. • Transfected SH and BAP31 co-localize in lung epithelial cells. • Endogenous BAP31 is pulled down by RSV SH protein. • BAP31 endodomain interacts with the N-terminal α-helix of SH protein in micelles. • This interaction is proposed to be a potential drug target

  5. Interaction between human BAP31 and respiratory syncytial virus small hydrophobic (SH) protein

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    Li, Yan; Jain, Neeraj; Limpanawat, Suweeraya; To, Janet [School of Biological Sciences, Nanyang Technological University, 637551 (Singapore); Quistgaard, Esben M. [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm (Sweden); Nordlund, Par [School of Biological Sciences, Nanyang Technological University, 637551 (Singapore); Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm (Sweden); Thanabalu, Thirumaran [School of Biological Sciences, Nanyang Technological University, 637551 (Singapore); Torres, Jaume, E-mail: jtorres@ntu.edu.sg [School of Biological Sciences, Nanyang Technological University, 637551 (Singapore)

    2015-08-15

    The small hydrophobic (SH) protein is a short channel-forming polypeptide encoded by the human respiratory syncytial virus (hRSV). Deletion of SH protein leads to the viral attenuation in mice and primates, and delayed apoptosis in infected cells. We have used a membrane-based yeast two-hybrid system (MbY2H) and a library from human lung cDNA to detect proteins that bind SH protein. This led to the identification of a membrane protein, B-cell associated protein 31 (BAP31). Transfected SH protein co-localizes with transfected BAP31 in cells, and pulls down endogenous BAP31. Titration of purified C-terminal endodomain of BAP31 against isotopically labeled SH protein in detergent micelles suggests direct interaction between the two proteins. Given the key role of BAP31 in protein trafficking and its critical involvement in pro- and anti-apoptotic pathways, this novel interaction may constitute a potential drug target. - Highlights: • A yeast two-hybrid system (MbY2H) detected BAP31 as a binder of RSV SH protein. • Transfected SH and BAP31 co-localize in lung epithelial cells. • Endogenous BAP31 is pulled down by RSV SH protein. • BAP31 endodomain interacts with the N-terminal α-helix of SH protein in micelles. • This interaction is proposed to be a potential drug target.

  6. Respiratory syncytial virus in adults with severe acute respiratory illness in a high HIV prevalence setting.

    Science.gov (United States)

    Moyes, Jocelyn; Walaza, Sibongile; Pretorius, Marthi; Groome, Michelle; von Gottberg, Anne; Wolter, Nicole; Haffejee, Sumayya; Variava, Ebrahim; Cohen, Adam L; Tempia, Stefano; Kahn, Kathleen; Dawood, Halima; Venter, Marietjie; Cohen, Cheryl; Madhi, Shabir A

    2017-10-01

    There are limited data on the epidemiology of respiratory syncytial virus (RSV) illness in HIV-infected adults or the elderly in Africa. We studied the epidemiology of RSV-associated severe acute respiratory illness (SARI) hospitalizations in adults in South Africa from 2009 through 2013. Individuals admitted to sentinel surveillance hospitals were investigated by respiratory tract swabs for RSV, using a multiplex real-time polymerase chain reaction assay. The incidence of RSV-associated SARI was calculated for the one site with population denominators. Of 7796 participants investigated, 329 (4%) tested positive for RSV. On multivariable analysis, HIV-infected individuals with RSV-associated SARI had greater odds of being in the age groups 18-44 and 45-64 years (odd ratios (OR) 26.3; 95% confidence interval (CI) 6.2-112.1 and OR 11.4; 95% CI 2.6-50.0) compared with those ≥65 years and being female (OR 2.7; 95% CI 1.4-5.4). The relative risk of hospitalization with RSV-associated SARI was 12-18 times higher in HIV infected individual compared to that of HIV-uninfected. The incidence of RSV-associated SARI was higher in HIV-infected individuals and those aged 65 years and older. Further studies are warranted to describe the disease association of RSV detected in adults with SARI. Copyright © 2017 The British Infection Association. All rights reserved.

  7. Human respiratory syncytial virus load normalized by cell quantification as predictor of acute respiratory tract infection.

    Science.gov (United States)

    Gómez-Novo, Miriam; Boga, José A; Álvarez-Argüelles, Marta E; Rojo-Alba, Susana; Fernández, Ana; Menéndez, María J; de Oña, María; Melón, Santiago

    2018-05-01

    Human respiratory syncytial virus (HRSV) is a common cause of respiratory infections. The main objective is to analyze the prediction ability of viral load of HRSV normalized by cell number in respiratory symptoms. A prospective, descriptive, and analytical study was performed. From 7307 respiratory samples processed between December 2014 to April 2016, 1019 HRSV-positive samples, were included in this study. Low respiratory tract infection was present in 729 patients (71.54%). Normalized HRSV load was calculated by quantification of HRSV genome and human β-globin gene and expressed as log10 copies/1000 cells. HRSV mean loads were 4.09 ± 2.08 and 4.82 ± 2.09 log10 copies/1000 cells in the 549 pharyngeal and 470 nasopharyngeal samples, respectively (P respiratory tract infection and 4.22 ± 2.28 log10 copies/1000 cells with upper respiratory tract infection or febrile syndrome (P < 0.05). A possible cut off value to predict LRTI evolution was tentatively established. Normalization of viral load by cell number in the samples is essential to ensure an optimal virological molecular diagnosis avoiding that the quality of samples affects the results. A high viral load can be a useful marker to predict disease progression. © 2018 Wiley Periodicals, Inc.

  8. Factors Affecting the Immunity to Respiratory Syncytial Virus: From Epigenetics to Microbiome

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    Wendy Fonseca

    2018-02-01

    Full Text Available Respiratory syncytial virus (RSV is a common pathogen that infects virtually all children by 2 years of age and is the leading cause of hospitalization of infants worldwide. While most children experience mild symptoms, some children progress to severe lower respiratory tract infection. Those children with severe disease have a much higher risk of developing childhood wheezing later in life. Many risk factors are known to result in exacerbated disease, including premature birth and early age of RSV infection, when the immune system is relatively immature. The development of the immune system before and after birth may be altered by several extrinsic and intrinsic factors that could lead to severe disease predisposition in children who do not exhibit any currently known risk factors. Recently, the role of the microbiome and the resulting metabolite profile has been an area of intense study in the development of lung disease, including viral infection and asthma. This review explores both known risk factors that can lead to severe RSV-induced disease as well as emerging topics in the development of immunity to RSV and the long-term consequences of severe infection.

  9. Respiratory syncytial virus increases lung cellular bioenergetics in neonatal C57BL/6 mice

    International Nuclear Information System (INIS)

    Alsuwaidi, Ahmed R.; Albawardi, Alia; Almarzooqi, Saeeda; Benedict, Sheela; Othman, Aws R.; Hartwig, Stacey M.; Varga, Steven M.; Souid, Abdul-Kader

    2014-01-01

    We have previously reported that lung cellular bioenergetics (cellular respiration and ATP) increased in 4–10 week-old BALB/c mice infected with respiratory syncytial virus (RSV). This study examined the kinetics and changes in cellular bioenergetics in ≤2-week-old C57BL/6 mice following RSV infection. Mice (5–14 days old) were inoculated intranasally with RSV and the lungs were examined on days 1–10 post-infection. Histopathology and electron microscopy revealed preserved pneumocyte architectures and organelles. Increased lung cellular bioenergetics was noted from days 1–10 post-infection. Cellular GSH remained unchanged. These results indicate that the increased lung cellular respiration (measured by mitochondrial O 2 consumption) and ATP following RSV infection is independent of either age or genetic background of the host. - Highlights: • RSV infection increases lung cellular respiration and ATP in neonatal C57BL/6 mice. • Increased lung cellular bioenergetics is a biomarker of RSV infection. • Lung cellular glutathione remains unchanged in RSV infection

  10. [Respiratory infections caused by respiratory syncytial virus in the adult population: description of 16 cases].

    Science.gov (United States)

    Reina, Jordi; López, Carla

    2013-08-17

    Respiratory infections of viral etiology are frequent in the adult population. Those caused by respiratory syncytial virus (RSV) are a little known entity. The aim of this study was to determine the clinical and epidemiological characteristics of adult patients with respiratory infection due to RSV. We performed a prospective study from October 2012 to March 2013 on respiratory infections caused by RSV. Viral detection was performed using a technique of reverse transcription polymerase chain reaction genomic amplification in real time. We diagnosed 16 patients, 12 (75%) requiring hospitalization. Patients were grouped into immunocompromised (7 [43.7%]) and immunocompetent cases (9 cases 56.3%]). The first group included 3 patients with HIV infection (42.8%) and 4 hematologic patients (57.2%). The second group included those who had a baseline disease, 5 cases (55.5%), and those who lacked it, 4 cases (44.4%), and did not require hospitalization. The main clinical manifestations of patients prompting them to attend the Emergency Department were cough (50%), dyspnea (43.5%), fever (25%), expectoration (25%) and flu symptoms (25%). The most frequent diagnoses at discharge were pneumonia (37.5%) and flu syndrome (31.2%). Respiratory infections caused by RSV represent a rare condition that mainly affects immunocompromised patients. The underlying pathology determines the evolution of the process, which is favorable except in cases of severe immunosuppression. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  11. Local interleukin-10 production during respiratory syncytial virus bronchiolitis is associated with post-bronchiolitis wheeze

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    Hodemaekers Hennie M

    2011-09-01

    Full Text Available Abstract Background Respiratory syncytial virus (RSV is the most common cause of bronchiolitis in infants. Following RSV bronchiolitis, 50% of children develop post-bronchiolitis wheeze (PBW. Animal studies have suggested that interleukin (IL-10 plays a critical role in the pathogenesis of RSV bronchiolitis and subsequent airway hyperresponsiveness. Previously, we showed that ex vivo monocyte IL-10 production is a predictor of PBW. Additionally, heterozygosity of the single-nucleotide polymorphism (SNP rs1800872 in the IL10 promoter region was associated with protection against RSV bronchiolitis. Methods This study aimed to determine the in vivo role of IL-10 in RSV pathogenesis and recurrent wheeze in a new cohort of 235 infants hospitalized for RSV bronchiolitis. IL-10 levels in nasopharyngeal aspirates (NPAs were measured at the time of hospitalization and the IL10 SNP rs1800872 genotype was determined. Follow-up data were available for 185 children (79%. Results Local IL-10 levels during RSV infection turned out to be higher in infants that later developed physician diagnosed PBW as compared to infants without PBW in the first year after RSV infection (958 vs 692 pg/ml, p = 0.02. The IL10 promoter SNP rs1800872 was not associated with IL-10 concentration in NPAs. Conclusion The relationship between high local IL-10 levels during the initial RSV infection and physician diagnosed PBW provides further evidence of the importance of the IL-10 response during RSV bronchiolitis.

  12. A review of palivizumab and emerging therapies for respiratory syncytial virus.

    Science.gov (United States)

    Shadman, Kristin A; Wald, Ellen R

    2011-11-01

    Respiratory syncytial virus (RSV) is an important pathogen in children and adults; however, current treatment options are primarily supportive. Palivizumab, the only approved specific monoclonal antibody for RSV is used prophylactically to reduce morbidity in a select population of high-risk children. The development and current use of palivizumab; the potential role of palivizumab as preventive therapy in patients with cystic fibrosis, asthma and compromised immune systems; and explores the limited research in which palivizumab has been used for treatment of RSV. The modified recommendations for the use of palivizumab espoused by the American Academy of Pediatrics and research on the cost-effectiveness of this product are presented. In addition, the authors discuss the development of enhanced monoclonal antibodies including motavizumab, which was recently denied FDA approval for preventative therapy. The authors explore the historical and current efforts to develop a vaccine targeting RSV. The current status of antiviral drug development is also reviewed. The literature search included RSV-Ig, palivizumab, and emerging drugs and vaccines for the treatment of RSV as keywords and titles from 1997 to 2011. Although there are potential drugs and vaccines in development to prevent or reduce the effects of RSV infection, palivizumab remains the only licensed product to reduce the severity of disease in high-risk pediatric patients.

  13. Respiratory syncytial virus increases lung cellular bioenergetics in neonatal C57BL/6 mice

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    Alsuwaidi, Ahmed R., E-mail: alsuwaidia@uaeu.ac.ae [Departments of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain (United Arab Emirates); Albawardi, Alia, E-mail: alia.albawardi@uaeu.ac.ae [Departments of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain (United Arab Emirates); Almarzooqi, Saeeda, E-mail: saeeda.almarzooqi@uaeu.ac.ae [Departments of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain (United Arab Emirates); Benedict, Sheela, E-mail: sheela.benedict@uaeu.ac.ae [Departments of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain (United Arab Emirates); Othman, Aws R., E-mail: aws.rashad@uaeu.ac.ae [Departments of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain (United Arab Emirates); Hartwig, Stacey M., E-mail: stacey-hartwig@uiowa.edu [Department of Microbiology, Department of Pathology and Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242 (United States); Varga, Steven M., E-mail: steven-varga@uiowa.edu [Department of Microbiology, Department of Pathology and Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242 (United States); Souid, Abdul-Kader, E-mail: asouid@uaeu.ac.ae [Departments of Pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain (United Arab Emirates)

    2014-04-15

    We have previously reported that lung cellular bioenergetics (cellular respiration and ATP) increased in 4–10 week-old BALB/c mice infected with respiratory syncytial virus (RSV). This study examined the kinetics and changes in cellular bioenergetics in ≤2-week-old C57BL/6 mice following RSV infection. Mice (5–14 days old) were inoculated intranasally with RSV and the lungs were examined on days 1–10 post-infection. Histopathology and electron microscopy revealed preserved pneumocyte architectures and organelles. Increased lung cellular bioenergetics was noted from days 1–10 post-infection. Cellular GSH remained unchanged. These results indicate that the increased lung cellular respiration (measured by mitochondrial O{sub 2} consumption) and ATP following RSV infection is independent of either age or genetic background of the host. - Highlights: • RSV infection increases lung cellular respiration and ATP in neonatal C57BL/6 mice. • Increased lung cellular bioenergetics is a biomarker of RSV infection. • Lung cellular glutathione remains unchanged in RSV infection.

  14. Multicenter Clinical Evaluation of the Alere i Respiratory Syncytial Virus Isothermal Nucleic Acid Amplification Assay.

    Science.gov (United States)

    Hassan, Ferdaus; Hays, Lindsay M; Bonner, Aleta; Bradford, Bradley J; Franklin, Ruffin; Hendry, Phyllis; Kaminetsky, Jed; Vaughn, Michael; Cieslak, Kristin; Moffatt, Mary E; Selvarangan, Rangaraj

    2018-03-01

    The Alere i respiratory syncytial virus (RSV) assay is an isothermal nucleic acid amplification test capable of detecting RSV directly from respiratory specimens, with results being available in ≤13 min after test initiation. The objective of this study was to evaluate the performance characteristics of the Alere i RSV assay in a point-of-care setting by using direct nasopharyngeal (NP) swab specimens (direct NP) and nasopharyngeal swab specimens eluted and transported in viral transport medium (VTM NP). The study was a prospective, multicenter, clinical trial conducted at 9 sites across the United States to evaluate the clinical performance of the Alere i RSV assay with respiratory specimens obtained from both children (age, 60 years). The performance of the Alere i RSV assay was compared with that of the reference method, the Prodesse ProFlu+ real-time reverse transcriptase PCR (RT-PCR) assay. All specimens with discrepant test results were tested further by a second FDA-cleared PCR assay (the Verigene respiratory virus plus nucleic acid test; Luminex Inc., TX). A total of 554 subjects with signs and symptoms of respiratory infections were enrolled, and respiratory samples were collected in this study. In comparison with the ProFlu+ real-time RT-PCR, the overall sensitivity and specificity of Alere i RSV assay for the detection of RSV were 98.6% (95% confidence interval [CI], 94.4 to 99.7%) and 98.0% (95% CI, 95.8 to 99.1%), respectively, for direct NP and 98.6% (95% CI, 94.4 to 99.7%) and 97.8% (95% CI, 95.5 to 98.9%), respectively, for VTM NP. The Alere i RSV is a highly sensitive and specific molecular assay ideal for rapid RSV detection in patients in the point-of-care setting due to its minimal hands-on time and rapid result availability. Copyright © 2018 American Society for Microbiology.

  15. Respiratory syncytial virus, adenoviruses, and mixed acute lower respiratory infections in children in a developing country.

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    Rodríguez-Martínez, Carlos E; Rodríguez, Diego Andrés; Nino, Gustavo

    2015-05-01

    There is growing evidence suggesting greater severity and worse outcomes in children with mixed as compared to single respiratory virus infections. However, studies that assess the risk factors that may predispose a child to a mixture of respiratory syncytial virus (RSV) and adenoviral infections, are scarce. In a retrospective cohort study, the study investigated the epidemiology of RSV and adenovirus infections and predictors of mixed RSV-adenoviral infections in young children hospitalized with acute lower respiratory infection in Bogota, Colombia, South America, over a 2-year period 2009-2011. Of a total of 5,539 children admitted with a diagnosis of acute lower respiratory infection, 2,267 (40.9%) who were positive for RSV and/or adenovirus were selected. Out the total number of cases, 1,416 (62.5%) infections occurred during the 3-month period from March to May, the first rainy season of Bogota, Colombia. After controlling for gender, month when the nasopharyngeal sample was taken, and other pre-existing conditions, it was found that an age greater than 6 months (OR:1.74; CI 95%:1.05-2.89; P = 0.030) and malnutrition as a comorbidity (OR:9.92; CI 95%:1.01-100.9; P = 0.049) were independent predictors of mixed RSV-adenoviral infections in the sample of patients. In conclusion, RSV and adenovirus are significant causes of acute lower respiratory infection in infants and young children in Bogota, Colombia, especially during the first rainy season. The identified predictors of mixed RSV-adenoviral infections should be taken into account when planning intervention, in order to reduce the burden of acute lower respiratory infection in young children living in the country. © 2015 Wiley Periodicals, Inc.

  16. Respiratory Syncytial Virus Aggravates Renal Injury through Cytokines and Direct Renal Injury

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    Songhui Zhai

    2016-09-01

    Full Text Available The purpose of this study was to investigate the relationship between renal injury and reinfection that is caused by respiratory syncytial virus (RSV and to analyze the mechanism of renal injury. Rats were repeatedly infected with RSV on days 4, 8, 14, and 28, then sacrificed and examined on day 56 after the primary infection. Renal injury was examined by transmission electron microscopy and histopathology. The F protein of RSV was detected in the renal tissue by indirect immunofluorescence. Proteinuria and urinary glycosaminoglycans (GAGs, serum levels of albumin, urea nitrogen, and creatinine, secretion of cytokines, T lymphocyte population and subsets, and dendritic cell (DC activation state were examined. The results showed that renal injury was more serious in the reinfection group than in the primary infection group. At a higher infection dose, 6×106 PFU, the renal injury was more severe, accompanied by higher levels of proteinuria and urinary GAGs excretion, and lower levels of serum albumin. Podocyte foot effacement was more extensive, and hyperplasia of mesangial cells and proliferation of mesangial matrix were observed. The maturation state of DCs was specific, compared with the primary infection. There was also a decrease in the ratio of CD4+ to CD8+T lymphocytes, due to an increase in the percentage of CD8+T lymphocytes and a decrease in the percentage of CD4+T lymphocytes, and a dramatic increase in the levels of IL-6 and IL-17. In terms of the different reinfection times, the day 14 reinfection group yielded the most serious renal injury and the most significant change in immune function. RSV F protein was still expressed in the glomeruli 56 days after RSV infection. Altogether, these results reveal that RSV infection could aggravate renal injury, which might be due to direct renal injury caused by RSV and the inflammatory lesions caused by the anti-virus response induced by RSV.

  17. Development and clinical applications of novel antibodies for prevention and treatment of respiratory syncytial virus infection.

    Science.gov (United States)

    Mejias, Asuncion; Garcia-Maurino, Cristina; Rodriguez-Fernandez, Rosa; Peeples, Mark E; Ramilo, Octavio

    2017-01-11

    Respiratory syncytial virus (RSV) remains a significant cause of morbidity and mortality in infants and young children, immunocompromised patients and the elderly. Despite the high disease burden, an effective and safe vaccine is lacking, although several candidates are currently in development. Current treatment for RSV infection remains largely supportive and RSV-specific options for prophylaxis are limited to palivizumab. In the past few years, novel therapeutic options including nanobodies, polyclonal and monoclonal antibodies have emerged and there are several products in preclinical and Phase-I, -II or -III clinical trials. The major target for antiviral drug development is the surface fusion (F) glycoprotein, which is crucial for the infectivity and pathogenesis of the virus. Solving the structures of the two conformations of the RSV F protein, the prefusion and postfusion forms, has revolutionized RSV research. It is now known that prefusion F is highly superior in inducing neutralizing antibodies. In this section we will review the stages of development and availability of different antibodies directed against RSV for the prevention and also for treatment of acute RSV infections. Some of these newer anti-RSV agents have shown enhanced potency, are being explored through alternative routes of administration, have improved pharmacokinetic profiles with an extended half-life, and may reduce design and manufacturing costs. Management strategies will require targeting not only high-risk populations (including adults or immunocompromised patients), but also previously healthy children who, in fact, represent the majority of children hospitalized with RSV infection. Following treated patients longitudinally is essential for determining the impact of these strategies on the acute disease as well as their possible long-term benefits on lung morbidity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Antibody Tracing, Seroepidemiology and Risk Factors of Bovine Respiratory Syncytial Virus and Bovine Adenovirus-3 in Dairy Holstein Farms

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    Mahsa FARZINPOUR

    2016-01-01

    Full Text Available Antibody tracing, risk factors and seroepidemiology of bovine respiratory syncytial virus and bovine adenovirus-3 were investigated in 22 Industrial and Semi-Industrial dairy Holstein farms. Serum samples (n=736 from various ages of unvaccinated cows were collected from May to September 2012. Risk factors including age, past history of respiratory diseases, amount of milk production, husbandry type and herd size were considered. Data were analyzed by Chi-square and logistic regression. Results indicated that the infection with some of individual viruses was related to past history of respiratory disease and herd size. No specific pattern was seen on the effect of level of milk production on seropositivity of animals. The seroprevalence for BRSV and BAV-3 were 89.1% and 88%, respectively. The present study indicates that infections of bovine respiratory viruses frequently occur in cattle of Fars province and the main viral cause of primary occurrence of respiratory diseases may be due to aforementioned viruses.

  19. Induction and Subversion of Human Protective Immunity: Contrasting Influenza and Respiratory Syncytial Virus

    Science.gov (United States)

    Ascough, Stephanie; Paterson, Suzanna; Chiu, Christopher

    2018-01-01

    Respiratory syncytial virus (RSV) and influenza are among the most important causes of severe respiratory disease worldwide. Despite the clinical need, barriers to developing reliably effective vaccines against these viruses have remained firmly in place for decades. Overcoming these hurdles requires better understanding of human immunity and the strategies by which these pathogens evade it. Although superficially similar, the virology and host response to RSV and influenza are strikingly distinct. Influenza induces robust strain-specific immunity following natural infection, although protection by current vaccines is short-lived. In contrast, even strain-specific protection is incomplete after RSV and there are currently no licensed RSV vaccines. Although animal models have been critical for developing a fundamental understanding of antiviral immunity, extrapolating to human disease has been problematic. It is only with recent translational advances (such as controlled human infection models and high-dimensional technologies) that the mechanisms responsible for differences in protection against RSV compared to influenza have begun to be elucidated in the human context. Influenza infection elicits high-affinity IgA in the respiratory tract and virus-specific IgG, which correlates with protection. Long-lived influenza-specific T cells have also been shown to ameliorate disease. This robust immunity promotes rapid emergence of antigenic variants leading to immune escape. RSV differs markedly, as reinfection with similar strains occurs despite natural infection inducing high levels of antibody against conserved antigens. The immunomodulatory mechanisms of RSV are thus highly effective in inhibiting long-term protection, with disturbance of type I interferon signaling, antigen presentation and chemokine-induced inflammation possibly all contributing. These lead to widespread effects on adaptive immunity with impaired B cell memory and reduced T cell generation and

  20. Induction and Subversion of Human Protective Immunity: Contrasting Influenza and Respiratory Syncytial Virus

    Directory of Open Access Journals (Sweden)

    Stephanie Ascough

    2018-03-01

    Full Text Available Respiratory syncytial virus (RSV and influenza are among the most important causes of severe respiratory disease worldwide. Despite the clinical need, barriers to developing reliably effective vaccines against these viruses have remained firmly in place for decades. Overcoming these hurdles requires better understanding of human immunity and the strategies by which these pathogens evade it. Although superficially similar, the virology and host response to RSV and influenza are strikingly distinct. Influenza induces robust strain-specific immunity following natural infection, although protection by current vaccines is short-lived. In contrast, even strain-specific protection is incomplete after RSV and there are currently no licensed RSV vaccines. Although animal models have been critical for developing a fundamental understanding of antiviral immunity, extrapolating to human disease has been problematic. It is only with recent translational advances (such as controlled human infection models and high-dimensional technologies that the mechanisms responsible for differences in protection against RSV compared to influenza have begun to be elucidated in the human context. Influenza infection elicits high-affinity IgA in the respiratory tract and virus-specific IgG, which correlates with protection. Long-lived influenza-specific T cells have also been shown to ameliorate disease. This robust immunity promotes rapid emergence of antigenic variants leading to immune escape. RSV differs markedly, as reinfection with similar strains occurs despite natural infection inducing high levels of antibody against conserved antigens. The immunomodulatory mechanisms of RSV are thus highly effective in inhibiting long-term protection, with disturbance of type I interferon signaling, antigen presentation and chemokine-induced inflammation possibly all contributing. These lead to widespread effects on adaptive immunity with impaired B cell memory and reduced T cell

  1. Immunogenicity of a modified-live virus vaccine against bovine viral diarrhea virus types 1 and 2, infectious bovine rhinotracheitis virus, bovine parainfluenza-3 virus, and bovine respiratory syncytial virus when administered intranasally in young calves.

    Science.gov (United States)

    Xue, Wenzhi; Ellis, John; Mattick, Debra; Smith, Linda; Brady, Ryan; Trigo, Emilio

    2010-05-14

    The immunogenicity of an intranasally-administered modified-live virus (MLV) vaccine in 3-8 day old calves was evaluated against bovine viral diarrhea virus (BVDV) types 1 and 2, infectious bovine rhinotracheitis (IBR) virus, parainfluenza-3 (PI-3) virus and bovine respiratory syncytial virus (BRSV). Calves were intranasally vaccinated with a single dose of a multivalent MLV vaccine and were challenged with one of the respective viruses three to four weeks post-vaccination in five separate studies. There was significant sparing of diseases in calves intranasally vaccinated with the MLV vaccine, as indicated by significantly fewer clinical signs, lower rectal temperatures, reduced viral shedding, greater white blood cell and platelet counts, and less severe pulmonary lesions than control animals. This was the first MLV combination vaccine to demonstrate efficacy against BVDV types 1 and 2, IBR, PI-3 and BRSV in calves 3-8 days of age. Copyright 2010 Elsevier Ltd. All rights reserved.

  2. Environmental exposure of primary care personnel to ribavirin aerosol when supervising treatment of infants with respiratory syncytial virus infections.

    Science.gov (United States)

    Rodriguez, W J; Bui, R H; Connor, J D; Kim, H W; Brandt, C D; Parrott, R H; Burch, B; Mace, J

    1987-01-01

    The potential exposure to ribavirin aerosol in the environment was assessed in nurses caring for infants and children with severe lower respiratory tract infections due to respiratory syncytial virus. Ribavirin aerosol was administered via a ventilator, oxygen tent, or oxygen hood. Participants worked directly with infants receiving ribavirin for 20.0 to 35.0 h over a 3-day period. No toxic or adverse effects of ribavirin aerosol were observed in any of the 19 nurses studied, and ribavirin was not detected in erythrocytes, plasma, or urine collected after the potential exposure period. PMID:3662474

  3. Respiratory syncytial virus groups A and B in Porto Alegre, Brazil, from 1990 to 1995 and 1998

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    Straliotto Selir M

    2001-01-01

    Full Text Available We analyzed the respiratory syncytial virus (RSV groups and their epidemiological pattern that were detected over the course of seven years in southern Brazil. The two RSV groups co-circulated each year, but frequencies of groups A and B varied both between and within yearly outbreaks. In 1991, group A predominated over group B (p=0.0016. RSV outbreaks analyzed showed a temperature-dependent pattern and no association with rainfall, similarly to other countries from southern South America. Knowledge of the variants is important in terms of both diagnosis and definition of a vaccine composition.

  4. Elevation of Serum Acid Sphingomyelinase Activity in Children with Acute Respiratory Syncytial Virus Bronchiolitis.

    Science.gov (United States)

    Yoshida, Shuichiro; Noguchi, Atsuko; Kikuchi, Wataru; Fukaya, Hiroshi; Igarashi, Kiyoshi; Takahashi, Tsutomu

    2017-12-01

    Acid sphingomyelinase (ASM) is a lysosomal enzyme that hydrolyzes sphingomyelin into ceramide, a bioactive lipid to regulate cellular physiological functions. Thus, ASM activation has been reported as a key event in pathophysiological reactions including inflammation, cytokine release, oxidative stress, and endothelial damage in human diseases. Since ASM activation is associated with extracellular ASM secretion through unknown mechanisms, it can be detected by recognizing the elevation of secretory ASM (S-ASM) activity. Serum S-ASM activity has been reported to increase in chronic diseases, acute cardiac diseases, and systemic inflammatory diseases. However, the serum S-ASM has not been investigated in common acute illness. This study was designed to evaluate serum S-ASM activity in children with common acute illness. Fifty children with common acute illness and five healthy children were included in this study. The patients were categorized into five groups based on clinical diagnoses: acute respiratory syncytial virus (RSV) bronchiolitis, adenovirus infection, streptococcal infection, asthma, and other infections due to unknown origin. The serum S-ASM activity was significantly elevated at 6.9 ± 1.6 nmol/0.1 mL/6 h in the group of acute RSV bronchiolitis patients compared with healthy children who had a mean level of 1.8 ± 0.8 nmol/0.1 mL/6 h (p ASM activity was not significantly elevated. The results suggest an association of ASM activation with RSV infection, a cause for common acute illness. This is the first report to describe the elevation of serum S-ASM activity in respiratory tract infection.

  5. Surfactant protein B polymorphisms are associated with severe respiratory syncytial virus infection, but not with asthma

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    Heinzmann Andrea

    2007-05-01

    Full Text Available Abstract Background Surfactant proteins (SP are important for the innate host defence and essential for a physiological lung function. Several linkage and association studies have investigated the genes coding for different surfactant proteins in the context of pulmonary diseases such as chronic obstructive pulmonary disease or respiratory distress syndrome of preterm infants. In this study we tested whether SP-B was in association with two further pulmonary diseases in children, i. e. severe infections caused by respiratory syncytial virus and bronchial asthma. Methods We chose to study five polymorphisms in SP-B: rs2077079 in the promoter region; rs1130866 leading to the amino acid exchange T131I; rs2040349 in intron 8; rs3024801 leading to L176F and rs3024809 resulting in R272H. Statistical analyses made use of the Armitage's trend test for single polymorphisms and FAMHAP and FASTEHPLUS for haplotype analyses. Results The polymorphisms rs3024801 and rs3024809 were not present in our study populations. The three other polymorphisms were common and in tight linkage disequilibrium with each other. They did not show association with bronchial asthma or severe RSV infection in the analyses of single polymorphisms. However, haplotypes analyses revealed association of SP-B with severe RSV infection (p = 0.034. Conclusion Thus our results indicate a possible involvement of SP-B in the genetic predisposition to severe RSV infections in the German population. In order to determine which of the three polymorphisms constituting the haplotypes is responsible for the association, further case control studies on large populations are necessary. Furthermore, functional analysis need to be conducted.

  6. Phylogeny and population dynamics of respiratory syncytial virus (Rsv) A and B.

    Science.gov (United States)

    Martinelli, Marianna; Frati, Elena Rosanna; Zappa, Alessandra; Ebranati, Erika; Bianchi, Silvia; Pariani, Elena; Amendola, Antonella; Zehender, Gianguglielmo; Tanzi, Elisabetta

    2014-08-30

    Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and young children. RSV is characterised by high variability, especially in the G glycoprotein, which may play a significant role in RSV pathogenicity by allowing immune evasion. To reconstruct the origin and phylodynamic history of RSV, we evaluated the genetic diversity and evolutionary dynamics of RSV A and RSV B isolated from children under 3 years old infected in Italy from 2006 to 2012. Phylogenetic analysis revealed that most of the RSV A sequences clustered with the NA1 genotype, and RSV B sequences were included in the Buenos Aires genotype. The mean evolutionary rates for RSV A and RSV B were estimated to be 2.1 × 10(-3) substitutions (subs)/site/year and 3.03 × 10(-3) subs/site/year, respectively. The time of most recent common ancestor for the tree root went back to the 1940s (95% highest posterior density-HPD: 1927-1951) for RSV A and the 1950s (95%HPD: 1951-1960) for RSV B. The RSV A Bayesian skyline plot (BSP) showed a decrease in transmission events ending in about 2005, when a sharp growth restored the original viral population size. RSV B BSP showed a similar trend. Site-specific selection analysis identified 10 codons under positive selection in RSV A sequences and only one site in RSV B sequences. Although RSV remains difficult to control due to its antigenic diversity, it is important to monitor changes in its coding sequences, to permit the identification of future epidemic strains and to implement vaccine and therapy strategies. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Exposure of neonates to Respiratory Syncytial Virus is critical in determining subsequent airway response in adults

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    Daly Melissa

    2006-08-01

    Full Text Available Abstract Background Respiratory syncytial virus (RSV is the most common cause of acute bronchiolitis in infants and the elderly. Furthermore, epidemiological data suggest that RSV infection during infancy is a potent trigger of subsequent wheeze and asthma development. However, the mechanism by which RSV contributes to asthma is complex and remains largely unknown. A recent study indicates that the age of initial RSV infection is a key factor in determining airway response to RSV rechallenge. We hypothesized that severe RSV infection during neonatal development significantly alters lung structure and the pulmonary immune micro-environment; and thus, neonatal RSV infection is crucial in the development of or predisposition to allergic inflammatory diseases such as asthma. Methods To investigate this hypothesis the present study was conducted in a neonatal mouse model of RSV-induced pulmonary inflammation and airway dysfunction. Seven-day-old mice were infected with RSV (2 × 105 TCID50/g body weight and allowed to mature to adulthood. To determine if neonatal RSV infection predisposed adult animals to enhanced pathophysiological responses to allergens, these mice were then sensitized and challenged with ovalbumin. Various endpoints including lung function, histopathology, cytokine production, and cellularity in bronchoalveolar lavage were examined. Results RSV infection in neonates alone led to inflammatory airway disease characterized by airway hyperreactivity, peribronchial and perivascular inflammation, and subepithelial fibrosis in adults. If early RSV infection was followed by allergen exposure, this pulmonary phenotype was exacerbated. The initial response to neonatal RSV infection resulted in increased TNF-α levels in bronchoalveolar lavage. Interestingly, increased levels of IL-13 and mucus hyperproduction were observed almost three months after the initial infection with RSV. Conclusion Neonatal RSV exposure results in long term

  8. [Respiratory syncytial virus outbreak in a tertiary hospital Neonatal Intensive Care Unit].

    Science.gov (United States)

    Moreno Parejo, Carlos; Morillo García, Aurea; Lozano Domínguez, Carmen; Carreño Ochoa, Concepción; Aznar Martín, Javier; Conde Herrera, Manuel

    2016-09-01

    Investigation and control of a respiratory syncytial virus (RSV) outbreak that affected the Neonatal Intensive Care Unit (NICU) of a university hospital from October to December 2012. Cohort study of children admitted to the NICU. The infection attack rate was calculated. A descriptive analysis of the cases and a multivariate analysis was performed using the variables that were shown to be risk factors for RSV infection. Preventive measures taken were: contact isolation; hand hygiene training and observation; exclusivity of a health team of nurses and physicians for positive cases, restrictions on visitor numbers; surveillance RSV testing, and palivizumab prophylaxis. The outbreak had three epidemic waves and 20 positive cases out of a total of 48 children admitted. The overall attack rate was 42%. Half of positive cases were children, with a median age of 36 days (p25=22, p75=58). The independent risk factors for RSV infection were birth weight below 1000 grams (OR=23.5; P=.002) and to have another nosocomial infection the week before the diagnosis of RSV infection (OR=19.98; P=.016). It was an outbreak with a high number of cases, due to the delay in notification, prolonged RSV carrier status, and low adherence to hand hygiene practice, which favoured the cross-transmission of infection. The most effective preventive measures were direct observation of hand hygiene and supervision of isolation measures. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Molecular Characterization of Human Respiratory Syncytial Virus in the Philippines, 2012-2013.

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    Rungnapa Malasao

    Full Text Available Human respiratory syncytial virus (HRSV is a major cause of acute lower respiratory tract infections in infants and children worldwide. We performed molecular analysis of HRSV among infants and children with clinical diagnosis of severe pneumonia in four study sites in the Philippines, including Biliran, Leyte, Palawan, and Metro Manila from June 2012 to July 2013. Nasopharyngeal swabs were collected and screened for HRSV using real-time polymerase chain reaction (PCR. Positive samples were tested by conventional PCR and sequenced for the second hypervariable region (2nd HVR of the G gene. Among a total of 1,505 samples, 423 samples were positive for HRSV (28.1%, of which 305 (72.1% and 118 (27.9% were identified as HRSV-A and HRSV-B, respectively. Two genotypes of HRSV-A, NA1 and ON1, were identified during the study period. The novel ON1 genotype with a 72-nucleotide duplication in 2nd HVR of the G gene increased rapidly and finally became the predominant genotype in 2013 with an evolutionary rate higher than the NA1 genotype. Moreover, in the ON1 genotype, we found positive selection at amino acid position 274 (p<0.05 and massive O- and N-glycosylation in the 2nd HVR of the G gene. Among HRSV-B, BA9 was the predominant genotype circulating in the Philippines. However, two sporadic cases of GB2 genotype were found, which might share a common ancestor with other Asian strains. These findings suggest that HRSV is an important cause of severe acute respiratory infection among children in the Philippines and revealed the emergence and subsequent predominance of the ON1 genotype and the sporadic detection of the GB2 genotype. Both genotypes were detected for the first time in the Philippines.

  10. Clinical Presentation and Birth Outcomes Associated with Respiratory Syncytial Virus Infection in Pregnancy.

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    Helen Y Chu

    Full Text Available Respiratory syncytial virus (RSV is the most important cause of viral pneumonia in children worldwide. A maternal vaccine may protect both the mother and infant from RSV illness. The epidemiology and clinical presentation of RSV in pregnant and postpartum women is not well-described.Data were collected from a prospective, randomized trial of influenza immunization in pregnant women in rural southern Nepal. Women were enrolled in their second trimester of pregnancy and followed until six months postpartum. Active weekly home-based surveillance for febrile respiratory illness was performed. Mid-nasal swabs collected with episodes of respiratory illness were tested for RSV by real-time polymerase chain reaction.RSV was detected in 14 (0.4% illness episodes in 3693 women over 3554 person-years of surveillance from 2011-2014. RSV incidence was 3.9/1000 person-years overall, and 11.8/1000 person-years between September and December. Seven (50% women sought care for RSV illness; none died. Of the 7 (50% illness episodes during pregnancy, all had live births with 2 (29% preterm births and a median birthweight of 3060 grams. This compares to 469 (13% preterm births and a median birthweight of 2790 grams in women without RSV during pregnancy. Of the 7 mothers with postpartum RSV infection, RSV was detected in 4 (57% of their infants.RSV was an uncommon cause of febrile respiratory illness in mothers during pregnancy in Nepal. These data will inform prevention and therapeutic strategies against RSV in resource-limited settings.

  11. When to perform urine cultures in respiratory syncytial virus-positive febrile older infants?

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    Kaluarachchi, Dinushan; Kaldas, Virginia; Erickson, Evelyn; Nunez, Randolph; Mendez, Magda

    2014-09-01

    Respiratory syncytial virus (RSV) infections are associated with clinically significant rate of urinary tract infections (UTIs) in young infants. Previous research investigating RSV infections and UTIs has been performed mainly in infants younger than 2 to 3 months and has not focused on the risk of UTI in infants 3 to 12 months. This study aimed to assess the rate of UTIs in febrile RSV-positive older infants admitted as inpatients and identify predictors of UTI in febrile RSV-positive older infants. This is a retrospective comparative study of febrile RSV-positive infants 0 to 12 months of age admitted to the inpatient pediatric unit of Lincoln Medical and Mental Health Center, Bronx, from September through April 2006 to 2012. Infants 3 to 12 months were considered the cases, and infants 0 to 3 months were the comparative group. The rate of UTIs between the 2 groups was compared. Univariate tests and multiple logistic regression were used to identify demographic/clinical factors associated with UTI in febrile RSV-positive older infants. A total of 414 RSV-positive febrile infants were enrolled including 297 infants 3 to 12 months of age. The rate of UTI in older infants was 6.1% compared with 6.8% in infants younger than 3 months. Positive urinalysis finding was an independent predictor of UTI (P = 0.003) in older infants. All 11 boys with UTI were uncircumcised, and none of the 51 circumcised boys had UTI. Demographic (race, sex, and age) and clinical factors (temperature, white blood cell count, and absolute neutrophil count) were not associated with UTI. Febrile older infants who are RSV positive have a clinically significant rate of UTIs. It seems prudent to examine the urine of these older infants. Positive urinalysis finding was a predictive factor of UTI. Circumcised boys are at a decreased risk of UTI, compared with uncircumcised boys.

  12. Respiratory syncytial virus-related encephalitis: magnetic resonance imaging findings with diffusion-weighted study

    International Nuclear Information System (INIS)

    Park, Arim; Suh, Sang-il; Seol, Hae-Young; Son, Gyu-Ri; Lee, Nam-Joon; Lee, Young Hen; Seo, Hyung Suk; Eun, Baik-Lin

    2014-01-01

    Respiratory syncytial virus (RSV) is a common pathogen causing acute respiratory infection in children. Herein, we describe the incidence and clinical and magnetic resonance imaging (MRI) findings of RSV-related encephalitis, a major neurological complication of RSV infection. We retrospectively reviewed the medical records and imaging findings of the patients over the past 7 years who are admitted to our medical center and are tested positive for RSV-RNA by reverse transcriptase PCR. In total, 3,856 patients were diagnosed with RSV bronchiolitis, and 28 of them underwent brain MRI for the evaluation of neurologic symptoms; 8 of these 28 patients had positive imaging findings. Five of these 8 patients were excluded because of non-RSV-related pathologies, such as subdural hemorrhage, brain volume loss due to status epilepticus, periventricular leukomalacia, preexisting ventriculomegaly, and hypoxic brain injury. The incidence of RSV-related encephalitis was as follows: 3/3,856 (0.08 %) of the patients are positive for RSV RNA, 3/28 (10.7 %) of the patient underwent brain MRI for neurological symptom, and 3/8 (37.5 %) of patients revealed abnormal MR findings. The imaging findings were suggestive of patterns of rhombenmesencephalitis, encephalitis with acute disseminated encephalomyelitis, and limbic encephalitis. They demonstrated no diffusion abnormality on diffusion-weighted image and symptom improvement on the follow-up study. Encephalitis with RSV bronchiolitis occurs rarely. However, on brain MRI performed upon suspicion of neurologic involvement, RSV encephalitis is not infrequently observed among the abnormal MR findings and may mimic other viral and limbic encephalitis. Physicians should be aware of this entity to ensure proper diagnosis and neurologic care of RSV-positive patients. (orig.)

  13. Respiratory syncytial virus-related encephalitis: magnetic resonance imaging findings with diffusion-weighted study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Arim; Suh, Sang-il; Seol, Hae-Young [Korea University College of Medicine, Department of Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of); Son, Gyu-Ri; Lee, Nam-Joon [Korea University College of Medicine, Department of Radiology, Korea University Anam Hospital, Seoul (Korea, Republic of); Lee, Young Hen; Seo, Hyung Suk [Korea University College of Medicine, Department of Radiology, Korea University Ansan Hospital, Gyeonggi-do (Korea, Republic of); Eun, Baik-Lin [Korea University College of Medicine, Department of Pediatrics, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2014-02-15

    Respiratory syncytial virus (RSV) is a common pathogen causing acute respiratory infection in children. Herein, we describe the incidence and clinical and magnetic resonance imaging (MRI) findings of RSV-related encephalitis, a major neurological complication of RSV infection. We retrospectively reviewed the medical records and imaging findings of the patients over the past 7 years who are admitted to our medical center and are tested positive for RSV-RNA by reverse transcriptase PCR. In total, 3,856 patients were diagnosed with RSV bronchiolitis, and 28 of them underwent brain MRI for the evaluation of neurologic symptoms; 8 of these 28 patients had positive imaging findings. Five of these 8 patients were excluded because of non-RSV-related pathologies, such as subdural hemorrhage, brain volume loss due to status epilepticus, periventricular leukomalacia, preexisting ventriculomegaly, and hypoxic brain injury. The incidence of RSV-related encephalitis was as follows: 3/3,856 (0.08 %) of the patients are positive for RSV RNA, 3/28 (10.7 %) of the patient underwent brain MRI for neurological symptom, and 3/8 (37.5 %) of patients revealed abnormal MR findings. The imaging findings were suggestive of patterns of rhombenmesencephalitis, encephalitis with acute disseminated encephalomyelitis, and limbic encephalitis. They demonstrated no diffusion abnormality on diffusion-weighted image and symptom improvement on the follow-up study. Encephalitis with RSV bronchiolitis occurs rarely. However, on brain MRI performed upon suspicion of neurologic involvement, RSV encephalitis is not infrequently observed among the abnormal MR findings and may mimic other viral and limbic encephalitis. Physicians should be aware of this entity to ensure proper diagnosis and neurologic care of RSV-positive patients. (orig.)

  14. Quantitative trait loci associated with the immune response to a bovine respiratory syncytial virus vaccine.

    Directory of Open Access Journals (Sweden)

    Richard J Leach

    Full Text Available Infectious disease is an important problem for animal breeders, farmers and governments worldwide. One approach to reducing disease is to breed for resistance. This linkage study used a Charolais-Holstein F2 cattle cross population (n = 501 which was genotyped for 165 microsatellite markers (covering all autosomes to search for associations with phenotypes for Bovine Respiratory Syncytial Virus (BRSV specific total-IgG, IgG1 and IgG2 concentrations at several time-points pre- and post-BRSV vaccination. Regions of the bovine genome which influenced the immune response induced by BRSV vaccination were identified, as well as regions associated with the clearance of maternally derived BRSV specific antibodies. Significant positive correlations were detected within traits across time, with negative correlations between the pre- and post-vaccination time points. The whole genome scan identified 27 Quantitative Trait Loci (QTL on 13 autosomes. Many QTL were associated with the Thymus Helper 1 linked IgG2 response, especially at week 2 following vaccination. However the most significant QTL, which reached 5% genome-wide significance, was on BTA 17 for IgG1, also 2 weeks following vaccination. All animals had declining maternally derived BRSV specific antibodies prior to vaccination and the levels of BRSV specific antibody prior to vaccination were found to be under polygenic control with several QTL detected.Heifers from the same population (n = 195 were subsequently immunised with a 40-mer Foot-and-Mouth Disease Virus peptide (FMDV in a previous publication. Several of these QTL associated with the FMDV traits had overlapping peak positions with QTL in the current study, including the QTL on BTA23 which included the bovine Major Histocompatibility Complex (BoLA, and QTL on BTA9 and BTA24, suggesting that the genes underlying these QTL may control responses to multiple antigens. These results lay the groundwork for future investigations to identify the

  15. Elevated temperature triggers human respiratory syncytial virus F protein six-helix bundle formation

    International Nuclear Information System (INIS)

    Yunus, Abdul S.; Jackson, Trent P.; Crisafi, Katherine; Burimski, Irina; Kilgore, Nicole R.; Zoumplis, Dorian; Allaway, Graham P.; Wild, Carl T.; Salzwedel, Karl

    2010-01-01

    Human respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract infection in infants, immunocompromised patients, and the elderly. The RSV fusion (F) protein mediates fusion of the viral envelope with the target cell membrane during virus entry and is a primary target for antiviral drug and vaccine development. The F protein contains two heptad repeat regions, HR1 and HR2. Peptides corresponding to these regions form a six-helix bundle structure that is thought to play a critical role in membrane fusion. However, characterization of six-helix bundle formation in native RSV F protein has been hindered by the fact that a trigger for F protein conformational change has yet to be identified. Here we demonstrate that RSV F protein on the surface of infected cells undergoes a conformational change following exposure to elevated temperature, resulting in the formation of the six-helix bundle structure. We first generated and characterized six-helix bundle-specific antibodies raised against recombinant peptides modeling the RSV F protein six-helix bundle structure. We then used these antibodies as probes to monitor RSV F protein six-helix bundle formation in response to a diverse array of potential triggers of conformational changes. We found that exposure of 'membrane-anchored' RSV F protein to elevated temperature (45-55 deg. C) was sufficient to trigger six-helix bundle formation. Antibody binding to the six-helix bundle conformation was detected by both flow cytometry and cell-surface immunoprecipitation of the RSV F protein. None of the other treatments, including interaction with a number of potential receptors, resulted in significant binding by six-helix bundle-specific antibodies. We conclude that native, untriggered RSV F protein exists in a metastable state that can be converted in vitro to the more stable, fusogenic six-helix bundle conformation by an increase in thermal energy. These findings help to better define the mechanism of

  16. Heparin octasaccharide decoy liposomes inhibit replication of multiple viruses

    Science.gov (United States)

    Hendricks, Gabriel L.; Velazquez, Lourdes; Pham, Serena; Qaisar, Natasha; Delaney, James C.; Viswanathan, Karthik; Albers, Leila; Comolli, James C.; Shriver, Zachary; Knipe, David M.; Kurt-Jones, Evelyn A.; Fygenson, Deborah K.; Trevejo, Jose M.

    2016-01-01

    Heparan sulfate (HS) is a ubiquitous glycosaminoglycan that serves as a cellular attachment site for a number of significant human pathogens, including respiratory syncytial virus (RSV), human parainfluenza virus 3 (hPIV3), and herpes simplex virus (HSV). Decoy receptors can target pathogens by binding to the receptor pocket on viral attachment proteins, acting as ‘molecular sinks’ and preventing the pathogen from binding to susceptible host cells. Decoy receptors functionalized with HS could bind to pathogens and prevent infection, so we generated decoy liposomes displaying HS-octasaccharide (HS-octa). These decoy liposomes significantly inhibited RSV, hPIV3, and HSV infectivity in vitro to a greater degree than the original HS-octa building block. The degree of inhibition correlated with the density of HS-octa displayed on the liposome surface. Decoy liposomes with HS-octa inhibited infection of viruses to a greater extent than either full-length heparin or HS-octa alone. Decoy liposomes were effective when added prior to infection or following the initial infection of cells in vitro. By targeting the well-conserved receptor-binding sites of HS-binding viruses, decoy liposomes functionalized with HS-octa are a promising therapeutic antiviral agent and illustrate the utility of the liposome delivery platform. PMID:25637710

  17. Radiographic and radionuclide lung perfusion imaging in healthy calves and calves naturally infected with bovine respiratory syncytial virus

    International Nuclear Information System (INIS)

    Verhoeff, J.; Brom, W.E. van den; Ingh, T.S.G.A.M. van den

    1992-01-01

    Nine calves between three and 18 weeks old with serologically confirmed natural bovine respiratory syncytial virus infection were examined clinically, radiographically and by radionuclide lung perfusion imaging. The results were compared with those from seven healthy calves. The diseased calves were euthanased and examined pathologically, virologically and bacteriologically. The clinical signs indicated that the disease was in an acute stage. Radiography of the diseased animals revealed cysts, corresponding morphologically with bullous emphysema, and infiltrations roughly corresponding in distribution with atelectatic and, or, pneumonic areas. Radionuclide lung perfusion imaging revealed no perfusion shifts between the left and right lungs and a normal perfusion pattern in five of the nine diseased calves. The abnormalities in the perfusion patterns of three calves were probably caused by anatomical disorders such as cysts and pleural adhesions, but no cause of the abnormality could be found in one calf. These findings suggest that in calves infected with bovine respiratory syncytial virus, the normal perfusion pattern is maintained until anatomical disorders occur. The pathological examination and radiography revealed that the cranioventral lung fields were particularly poorly ventilated. This finding and the normal perfusion pattern indicate that these parts of the lungs are probably the sites where shuntings and perfusion-ventilation mismatchings occur

  18. An experimental infection model for reproduction of calf pneumonia with bovine respiratory syncytial virus (BRSV) based on one combined exposure of calves

    DEFF Research Database (Denmark)

    Tjørnehøj, Kirsten; Uttenthal, Åse; Viuff, B.

    2003-01-01

    Bovine respiratory syncytial virus (BRSV) has been recognised as an important pathogen in calf pneumonia for 30 years, but surprisingly few effective infection models for studies of the immune response and the pathogenesis in the natural host have been established. We present a reproducible...... disease. This model is a valuable tool for the study of the pathogenesis of BRSV and for vaccine efficacy studies....

  19. A bovine respiratory syncytial virus strain with mutations in subgroup-specific antigenic domains of the G protein induces partial heterologous protection in cattle

    NARCIS (Netherlands)

    Schrijver, R.S.; Langedijk, J.P.M.; Middel, W.G.J.; Kramps, J.A.; Rijsewijk, F.A.M.; Oirschot, van J.T.

    1998-01-01

    Bovine respiratory syncytial virus (BRSV) strains are tentatively divided in subgroups A, AB and B, based on antigenic differences of the G protein. A Dutch BRSV strain (Waiboerhoeve: WBH), could not be assigned to one of the subgroups, because the strain did not react with any monoclonal antibody

  20. Characterization of the CD8(+)T cell responses directed against respiratory syncytial virus during primary and secondary infection in C57BL/6 mice

    NARCIS (Netherlands)

    Lukens, M.V.; Claassen, E.A.W.; Graaff, de P.M.A.; Dijk, van M.E.A.; Hoogerhout, P.; Toebes, M.; Schumacher, T.N.; Most, van der R.G.; Kimpen, J.L.L.; Bleek, van G.M.

    2006-01-01

    The BALB/c mouse model for human respiratory syncytial virus infection has contributed significantly to our understanding of the relative role for CD4+ and CD8+ T cells to immune protection and pathogenic immune responses. To enable comparison of RSV-specific T cell responses in different mouse

  1. Investigation of the presence of human or bovine respiratory syncytial virus in the lungs of mink (Neovison vison) with hemorrhagic pneumonia due to Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Salomonsen, Charlotte Mark; Breum, Solvej Østergaard; Larsen, Lars Erik

    2012-01-01

    Background Hemorrhagic pneumonia is a disease of farmed mink (Neovison vison) caused by Pseudomonas aeruginosa. The disease is highly seasonal in Danish mink with outbreaks occurring almost exclusively in the autumn. Human respiratory syncytial virus (RSV) has been shown to augment infection with...

  2. High Incidence of Recurrent Wheeze in Children With Down Syndrome With and Without Previous Respiratory Syncytial Virus Lower Respiratory Tract Infection

    NARCIS (Netherlands)

    Bloemers, B.; van Furth, A.M.; Weijerman, M.E.; Gemke, R.J.B.J.; Broers, C.J.M.; Kimpen, J.L.L.; Bont, L.

    2010-01-01

    Background: Respiratory syncytial virus (RSV)-induced lower respiratory tract infection (LRTI) is associated with the subsequent development of recurrent wheeze. In a recent study, we found a high incidence (9.9%) of hospitalization for RSV-induced LRTI among children with Down syndrome (DS),

  3. Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in young children in 2015 : A systematic review and modelling study

    NARCIS (Netherlands)

    Shi, Ting; McAllister, David A.; O'Brien, Katherine L.; Simoes, Eric A. F.; Madhi, Shabir A.; Gessner, Bradford D.; Polack, Fernando P.; Balsells, Evelyn; Acacio, Sozinho; Aguayo, Claudia; Alassani, Issifou; Ali, Asad; Antonio, Martin; Awasthi, Shally; Awori, Juliet O.; Azziz-Baumgartner, Eduardo; Baggett, Henry C.; Baillie, Vicky L.; Balmaseda, Angel; Barahona, Alfredo; Basnet, Sudha; Bassat, Quique; Basualdo, Wilma; Bigogo, Godfrey; Bont, Louis; Breiman, Robert F.; Brooks, W. Abdullah; Broor, Shobha; Bruce, Nigel; Bruden, Dana; Buchy, Philippe; Campbell, Stuart; Carosone-Link, Phyllis; Chadha, Mandeep; Chipeta, James; Chou, Monidarin; Clara, Wilfrido; Cohen, Cheryl; de Cuellar, Elizabeth; Dang, Duc Anh; Dash-yandag, Budragchaagiin; Deloria-Knoll, Maria; Dherani, Mukesh; Eap, Tekchheng; Ebruke, Bernard E.; Echavarria, Marcela; de Freitas Lázaro Emediato, Carla Cecília; Fasce, Rodrigo A.; Feikin, Daniel R.; Feng, Luzhao; Gentile, Angela; Gordon, Aubree; Goswami, Doli; Goyet, Sophie; Groome, Michelle J; Halasa, Natasha; Hirve, Siddhivinayak; Homaira, Nusrat; Howie, Stephen R.C.; Jara, Jorge; Jroundi, Imane; Kartasasmita, Cissy B.; Khuri-Bulos, Najwa; Kotloff, Karen L.; Krishnan, Anand; Libster, Romina; Lopez, Olga; Lucero, Marilla G.; Lucion, Florencia; Lupisan, Socorro P.; Marcone, Debora N.; McCracken, John P.; Mejia, Mario; Moisi, Jennifer C.; Montgomery, Joel M.; Moore, David P.; Moraleda, Cinta; Moyes, Jocelyn; Munywoki, Patrick; Mutyara, Kuswandewi; Nicol, Mark P.; Nokes, D. James; Nymadawa, Pagbajabyn; da Costa Oliveira, Maria Tereza; Oshitani, Histoshi; Pandey, Nitin; Paranhos-Baccalà, Gláucia; Phillips, Lia N.; Picot, Valentina Sanchez; Rahman, Mustafizur; Rakoto-Andrianarivelo, Mala; Rasmussen, Zeba A.; Rath, Barbara A.; Robinson, Annick; Romero, Candice; Russomando, Graciela; Salimi, Vahid; Sawatwong, Pongpun; Scheltema, Nienke; Schweiger, Brunhilde; Scott, J. Anthony G.; Seidenberg, Phil; Shen, Kunling; Singleton, Rosalyn; Sotomayor, Viviana; Strand, Tor A.; Sutanto, Agustinus; Sylla, Mariam; Tapia, Milagritos D.; Thamthitiwat, Somsak; Thomas, Elizabeth D.; Tokarz, Rafal; Turner, Claudia; Venter, Marietjie; Waicharoen, Sunthareeya; Wang, Jianwei; Watthanaworawit, Wanitda; Yoshida, Lay Myint; Yu, Hongjie; Zar, Heather J.; Campbell, Harry; Nair, Harish

    2017-01-01

    Background: We have previously estimated that respiratory syncytial virus (RSV) was associated with 22% of all episodes of (severe) acute lower respiratory infection (ALRI) resulting in 55 000 to 199 000 deaths in children younger than 5 years in 2005. In the past 5 years, major research activity on

  4. Identification of a New Ribonucleoside Inhibitor of Ebola Virus Replication

    Directory of Open Access Journals (Sweden)

    Olivier Reynard

    2015-12-01

    Full Text Available The current outbreak of Ebola virus (EBOV in West Africa has claimed the lives of more than 15,000 people and highlights an urgent need for therapeutics capable of preventing virus replication. In this study we screened known nucleoside analogues for their ability to interfere with EBOV replication. Among them, the cytidine analogue β-d-N4-hydroxycytidine (NHC demonstrated potent inhibitory activities against EBOV replication and spread at non-cytotoxic concentrations. Thus, NHC constitutes an interesting candidate for the development of a suitable drug treatment against EBOV.

  5. Investigation of radiation enhanced reactivation of cytoplasmic replicating human virus

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Haynes, K.F.; Stafford, J.E.

    1976-01-01

    When monolayers of CV-1 monkey kidney cells were exposed to ultraviolet (uv) radiation (0 to 200 erg/nm 2 ) or x rays (0 to 10 krads) before infection with uv-irradiated herpes simplex virus, an increase in the infectivity of this nuclear replicating virus occurred as measured by plaque formation. These phenomena are known as uv (Weigle) reactivation (WR) and x-ray reactivation (x-ray R). In this study the presence of WR and x-ray R was examined in CV-1 cells infected with uv-irradiated vaccinia virus or poliovirus, both cytoplasmic replicating viruses. Little or no WR or x-ray R was observed for either of these viruses. These results suggest that WR and x-ray R in mammalian cells may be restricted to viruses which are synthesized in the cell nucleus

  6. A safe and efficient BCG vectored vaccine to prevent the disease caused by the human Respiratory Syncytial Virus.

    Science.gov (United States)

    Rey-Jurado, Emma; Soto, Jorge; Gálvez, Nicolás; Kalergis, Alexis M

    2017-09-02

    The human Respiratory Syncytial Virus (hRSV) causes lower respiratory tract infections including pneumonia and bronchiolitis. Such infections also cause a large number of hospitalizations and affects mainly newborns, young children and the elderly worldwide. Symptoms associated with hRSV infection are due to an exacerbated immune response characterized by low levels of IFN-γ, recruitment of neutrophils and eosinophils to the site of infection and lung damage. Although hRSV is a major health problem, no vaccines are currently available. Different immunization approaches have been developed to achieve a vaccine that activates the immune system, without triggering an unbalanced inflammation. These approaches include live attenuated vaccine, DNA or proteins technologies, and the use of vectors to express proteins of the virus. In this review, we discuss the host immune response to hRSV and the immunological mechanisms underlying an effective and safe BCG vectored vaccine against hRSV.

  7. Experiments toward the development of a radioimmunoassay for the detection of serum antibodies for the respiratory syncytial virus

    International Nuclear Information System (INIS)

    Heizmann, W.R.

    1982-01-01

    In order to detect an infection by the respiratory syncytial virus (RSV) quickly and safely, a radioimmunassay (RIA) should be developed. Various antigen preparations were compared to one another. The immune serums used in the RIA came from guinea pigs with a RSV antibody titer of up to 320 in the complement binding reaction. A number of observations lead to the discussion of the possibility of the formation (incomplete) of cross-reactive antibodies between virus and host cell. This hypothesis could be well supported through references in the literature. Under the assumption of the existence of cross-reactive antibodies, a further model of the pathogenesis of the RSV illness allows itself to be developed, which could be preceived as an illness with autoimmune components. With this model the varying courses of this disease in different age groups can be easily explained. (orig.) [de

  8. Replication of avian influenza A viruses in mammals.

    OpenAIRE

    Hinshaw, V S; Webster, R G; Easterday, B C; Bean, W J

    1981-01-01

    The recent appearance of an avian influenza A virus in seals suggests that viruses are transmitted from birds to mammals in nature. To examine this possibility, avian viruses of different antigenic subtypes were evaluated for their ability to replicate in three mammals-pigs, ferrets, and cats. In each of these mammals, avian strains replicated to high titers in the respiratory tract (10(5) to 10(7) 50% egg infective doses per ml of nasal wash), with peak titers at 2 to 4 days post-inoculation...

  9. [Risk factors for acute respiratory syncytial virus infection of lower respiratory tract in hospitalized infants].

    Science.gov (United States)

    Zhang, Xiaobo; Liu, Lijuan; Shi, Peng; Jiang, Gaoli; Jia, Pin; Wang, Chuankai; Wang, Libo; Qian, Liling

    2014-05-01

    To investigate the clinical epidemiologic characteristics and analyze risk factors for acute respiratory syncytial virus (RSV) infection in hospitalized infants with acute lower respiratory tract infection (ALRI). ALRI infants admitted to Children's Hospital of Fudan University from March 1st, 2011 to February 29th, 2012, were enrolled in this study. Patient information included demographic characteristics, feeding history, family status, clinical presentation, accessory examination, treatment and prognosis. According to the etiology of ALRI infants, we compared the seasonal distribution, demographic characteristics, household characteristics and underlying diseases between RSV-positive patients and RSV-negative patients. Univariate and multiple Logistic regression analyses were used to determine factors that were associated with risk of RSV infection. Among 1 726 ALRI infants, there were 913 RSV-positive infants (52.9%). The occurrence of RSV infection had a seasonal variation, with a peak in winter (59.1%). The median (P25, P75) age of RSV infants was 64 (21-155) days. The gestational age (GA) and body weight (BW) was (37.5 ± 2.4) weeks and (3.07 ± 0.66) kg, respectively. The male/female ratio among these was 1.9: 1. RSV infection was more popular among infants in the families with smoking members, crowded living conditions, history of atopic mother. Differences of the proportion of patients with underlying disease between RSV-positive and negative groups were statistically significant (59.4% vs. 54.2%, P infection were: GAinfection (OR = 1.351, 95%CI: 1.024-1.783; OR = 1.713, 95%CI: 1.332-2.204). Multivariate logistic regression determined the factors increasing the risk of RSV infection were: underlying CHD (OR = 1.298, 95%CI: 1.002-1.681), mother with atopic diseases (OR = 1.766, 95%CI: 1.237-2.520), autumn or winter infection (OR = 1.481, 95%CI: 1.105-1.985; OR = 1.766, 95%CI: 1.358-2.296). The prevalence of RSV infection was the highest in winter, while

  10. Structure-Based Design of Head-Only Fusion Glycoprotein Immunogens for Respiratory Syncytial Virus.

    Directory of Open Access Journals (Sweden)

    Jeffrey C Boyington

    Full Text Available Respiratory syncytial virus (RSV is a significant cause of severe respiratory illness worldwide, particularly in infants, young children, and the elderly. Although no licensed vaccine is currently available, an engineered version of the metastable RSV fusion (F surface glycoprotein-stabilized in the pre-fusion (pre-F conformation by "DS-Cav1" mutations-elicits high titer RSV-neutralizing responses. Moreover, pre-F-specific antibodies, often against the neutralization-sensitive antigenic site Ø in the membrane-distal head region of trimeric F glycoprotein, comprise a substantial portion of the human response to natural RSV infection. To focus the vaccine-elicited response to antigenic site Ø, we designed a series of RSV F immunogens that comprised the membrane-distal head of the F glycoprotein in its pre-F conformation. These "head-only" immunogens formed monomers, dimers, and trimers. Antigenic analysis revealed that a majority of the 70 engineered head-only immunogens displayed reactivity to site Ø-targeting antibodies, which was similar to that of the parent RSV F DS-Cav1 trimers, often with increased thermostability. We evaluated four of these head-only immunogens in detail, probing their recognition by antibodies, their physical stability, structure, and immunogenicity. When tested in naïve mice, a head-only trimer, half the size of the parent RSV F trimer, induced RSV titers, which were statistically comparable to those induced by DS-Cav1. When used to boost DS-Cav1-primed mice, two head-only RSV F immunogens, a dimer and a trimer, boosted RSV-neutralizing titers to levels that were comparable to those boosted by DS-Cav1, although with higher site Ø-directed responses. Our results provide proof-of-concept for the ability of the smaller head-only RSV F immunogens to focus the vaccine-elicited response to antigenic site Ø. Decent primary immunogenicity, enhanced physical stability, potential ease of manufacture, and potent

  11. Spatial patterns of Bovine Corona Virus and Bovine Respiratory Syncytial Virus in the Swedish beef cattle population

    Directory of Open Access Journals (Sweden)

    Björkman Camilla

    2010-05-01

    Full Text Available Abstract Background Both bovine coronavirus (BCV and bovine respiratory syncytial virus (BRSV infections are currently wide-spread in the Swedish dairy cattle population. Surveys of antibody levels in bulk tank milk have shown very high nationwide prevalences of both BCV and BRSV, with large variations between regions. In the Swedish beef cattle population however, no investigations have yet been performed regarding the prevalence and geographical distribution of BCV and BRSV. A cross-sectional serological survey for BCV and BRSV was carried out in Swedish beef cattle to explore any geographical patterns of these infections. Methods Blood samples were collected from 2,763 animals located in 2,137 herds and analyzed for presence of antibodies to BCV and BRSV. Moran's I was calculated to assess spatial autocorrelation, and identification of geographical cluster was performed using spatial scan statistics. Results Animals detected positive to BCV or BRSV were predominately located in the central-western and some southern parts of Sweden. Moran's I indicated global spatial autocorrelation. BCV and BRSV appeared to be spatially related: two areas in southern Sweden (Skaraborg and Skåne had a significantly higher prevalence of BCV (72.5 and 65.5% respectively; almost the same two areas were identified as being high-prevalence clusters for BRSV (69.2 and 66.8% respectively. An area in south-east Sweden (Kronoberg-Blekinge had lower prevalences for both infections than expected (23.8 and 20.7% for BCV and BRSV respectively. Another area in middle-west Sweden (Värmland-Dalarna had also a lower prevalence for BRSV (7.9%. Areas with beef herd density > 10 per 100 km2 were found to be at significantly higher risk of being part of high-prevalence clusters. Conclusion These results form a basis for further investigations of between-herds dynamics and risk factors for these infections in order to design effective control strategies.

  12. Cytoplasmic ATR Activation Promotes Vaccinia Virus Genome Replication

    Directory of Open Access Journals (Sweden)

    Antonio Postigo

    2017-05-01

    Full Text Available In contrast to most DNA viruses, poxviruses replicate their genomes in the cytoplasm without host involvement. We find that vaccinia virus induces cytoplasmic activation of ATR early during infection, before genome uncoating, which is unexpected because ATR plays a fundamental nuclear role in maintaining host genome integrity. ATR, RPA, INTS7, and Chk1 are recruited to cytoplasmic DNA viral factories, suggesting canonical ATR pathway activation. Consistent with this, pharmacological and RNAi-mediated inhibition of canonical ATR signaling suppresses genome replication. RPA and the sliding clamp PCNA interact with the viral polymerase E9 and are required for DNA replication. Moreover, the ATR activator TOPBP1 promotes genome replication and associates with the viral replisome component H5. Our study suggests that, in contrast to long-held beliefs, vaccinia recruits conserved components of the eukaryote DNA replication and repair machinery to amplify its genome in the host cytoplasm.

  13. Phosphorylation of the human respiratory syncytial virus P protein mediates M2-2 regulation of viral RNA synthesis, a process that involves two P proteins.

    Science.gov (United States)

    Asenjo, Ana; Villanueva, Nieves

    2016-01-04

    The M2-2 protein regulates the balance between human respiratory syncytial virus (HRSV) transcription and replication. Here it is shown that M2-2 mediated transcriptional inhibition is managed through P protein phosphorylation. Transcription inhibition by M2-2 of the HRSV based minigenome pRSVluc, required P protein phosphorylation at serines (S) in positions 116, 117, 119 and increased inhibition is observed if S232 or S237 is also phosphorylated. Phosphorylation of these residues is required for viral particle egression from infected cells. Viral RNA synthesis complementation assays between P protein variants, suggest that two types of P proteins participate in the process as components of RNA dependent RNA polymerase (RdRp). Type I is only functional when, as a homotetramer, it is bound to N and L proteins through residues 203-241. Type II is functionally independent of these interactions and binds to N protein at a region outside residues 232-241. P protein type I phosphorylation at S116, S117 and S119, did not affect the activity of RdRp but this phosphorylation in type II avoids its interaction with N protein and impairs RdRp functionality for transcription and replication. Structural changes in the RdRp, mediated by phosphorylation turnover at the indicated residues, in the two types of P proteins, may result in a fine adjustment, late in the infectious cycle, of transcription, replication and progression in the morphogenetic process that ends in egression of the viral particles from infected cells. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Hepatitis C Virus Replication Depends on Endosomal Cholesterol Homeostasis.

    Science.gov (United States)

    Stoeck, Ina Karen; Lee, Ji-Young; Tabata, Keisuke; Romero-Brey, Inés; Paul, David; Schult, Philipp; Lohmann, Volker; Kaderali, Lars; Bartenschlager, Ralf

    2018-01-01

    Similar to other positive-strand RNA viruses, hepatitis C virus (HCV) causes massive rearrangements of intracellular membranes, resulting in a membranous web (MW) composed of predominantly double-membrane vesicles (DMVs), the presumed sites of RNA replication. DMVs are enriched for cholesterol, but mechanistic details on the source and recruitment of cholesterol to the viral replication organelle are only partially known. Here we focused on selected lipid transfer proteins implicated in direct lipid transfer at various endoplasmic reticulum (ER)-membrane contact sites. RNA interference (RNAi)-mediated knockdown identified several hitherto unknown HCV dependency factors, such as steroidogenic acute regulatory protein-related lipid transfer domain protein 3 (STARD3), oxysterol-binding protein-related protein 1A and -B (OSBPL1A and -B), and Niemann-Pick-type C1 (NPC1), all residing at late endosome and lysosome membranes and required for efficient HCV RNA replication but not for replication of the closely related dengue virus. Focusing on NPC1, we found that knockdown or pharmacological inhibition caused cholesterol entrapment in lysosomal vesicles concomitant with decreased cholesterol abundance at sites containing the viral replicase factor NS5A. In untreated HCV-infected cells, unesterified cholesterol accumulated at the perinuclear region, partially colocalizing with NS5A at DMVs, arguing for NPC1-mediated endosomal cholesterol transport to the viral replication organelle. Consistent with cholesterol being an important structural component of DMVs, reducing NPC1-dependent endosomal cholesterol transport impaired MW integrity. This suggests that HCV usurps lipid transfer proteins, such as NPC1, at ER-late endosome/lysosome membrane contact sites to recruit cholesterol to the viral replication organelle, where it contributes to MW functionality. IMPORTANCE A key feature of the replication of positive-strand RNA viruses is the rearrangement of the host cell

  15. Radiation enhanced reactivation of nuclear replicating mammalian viruses

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Lytle, C.D.

    1977-01-01

    When CV-1 monkey kidney cells were UV-irradiated (0 to 18 J/m 2 ) or X-irradiated (0 to 10 krads) before infection with UV-irradiated simian adenovirus 7 (SA7) or simian virus 40 (SV40), increases in the infectivity of these nuclear replicating viruses as measured by plaque formation were observed. These radiation enhanced reactivations, UV enhanced reactivation (UVER) and X-ray enhanced reactivation (X-ray ER), occurred both when virus infection immediately followed irradiation of the cells (except for X-ray ER with SA7) and when virus infection was delayed until 3 to 5 days after cell irradiation. While there was little difference in the levels of reactivation of UV-irradiated SV40 between immediate and delayed infection, delayed infection resulted in higher levels of reactivation of SA7. X-ray enhanced reactivation of UV-irradiated Herpes simplex virus persisted for several days but did not increase. Thus, X-ray enhanced and UV enhanced reactivations of these mammalian viruses were relatively long-lived effects. Essentially no UVER or X-ray ER was found in CV-1 cells for either immediate or delayed infection with UV-irradiated vaccinia virus or poliovirus, both of which replicate in the cell cytoplasm. These results suggest UVER and X-ray ER in mammalian cells may be restricted to viruses which are replicated in the cell nucleus. (author)

  16. The cytoprotective enzyme heme oxygenase-1 suppresses Ebola virus replication.

    Science.gov (United States)

    Hill-Batorski, Lindsay; Halfmann, Peter; Neumann, Gabriele; Kawaoka, Yoshihiro

    2013-12-01

    Ebola virus (EBOV) is the causative agent of a severe hemorrhagic fever in humans with reported case fatality rates as high as 90%. There are currently no licensed vaccines or antiviral therapeutics to combat EBOV infections. Heme oxygenase-1 (HO-1), an enzyme that catalyzes the rate-limiting step in heme degradation, has antioxidative properties and protects cells from various stresses. Activated HO-1 was recently shown to have antiviral activity, potently inhibiting the replication of viruses such as hepatitis C virus and human immunodeficiency virus. However, the effect of HO-1 activation on EBOV replication remains unknown. To determine whether the upregulation of HO-1 attenuates EBOV replication, we treated cells with cobalt protoporphyrin (CoPP), a selective HO-1 inducer, and assessed its effects on EBOV replication. We found that CoPP treatment, pre- and postinfection, significantly suppressed EBOV replication in a manner dependent upon HO-1 upregulation and activity. In addition, stable overexpression of HO-1 significantly attenuated EBOV growth. Although the exact mechanism behind the antiviral properties of HO-1 remains to be elucidated, our data show that HO-1 upregulation does not attenuate EBOV entry or budding but specifically targets EBOV transcription/replication. Therefore, modulation of the cellular enzyme HO-1 may represent a novel therapeutic strategy against EBOV infection.

  17. ROLE OF PREEXISTING VIRUS-SPECIFIC IgG IN PRIMARY DISEASE AND IN REINFECTION WITH RESPIRATORY SYNCYTIAL VIRUS

    Directory of Open Access Journals (Sweden)

    V. Z. Krivitskaya

    2012-01-01

    Full Text Available Abstract. The aim of the study is evaluation of links between presence in blood of specific pre-existing IgG to respiratory-syncytial virus (RSV, clinical course of RSV infection and character specific to RSV humoral immune response in patients of different ages. The antibodies were detected by ELISA using whole RS virus or synthetic peptides corresponded to the selected determinants of the envelope RSV proteins. It was shown that RS specific maternal IgG antibodies passively transferred to babies in utero can circulate in the blood up to 10 months of life. The analysis of paired sera of 45 babies in the age of 1–10 months revealed firstly that presence of maternal IgG specific antibodies to the conservative B-cell immunogenic determinants of the F-protein (amino acids 221–232 and/or the G-protein (amino acids 152–164 and 184–198 is coupled with more high morbidity of primary RSV infection (89% versus 56%, p = 0.023, and also with more high frequency of complicated by bronchus obstruction course of the disease (81% versus 20%, р = 0.001 in compare with babies who were serologically negative to the maternal determinants specific antibodies. The correlation analysis has shown that the high presence of maternal determinant-specific IgG in the blood in babies till 10 months of life is associated in the case of primary infection with disbalance of humoral anti-viral immune response: intensive synthesis of serum RSV IgA. This is evidence of complicated course of infection with simultaneous suppression of response to RSV specific IgG. As opposed to the primary RSV infection in patients older than 3 years (n = 121 it was not detected links between anamnestic determinant-specific IgG synthesized by own immune system as the results of previous disease episodes and synthesis of anti-RSV IgG, IgM, IgE and IgA in RSV re-infections. In the contrast to babies in more older patients the feedback connection between level of pre-existing determinant

  18. Epidemiological and molecular surveillance of influenza and respiratory syncytial viruses in children with acute respiratory infections (2004/2005 season

    Directory of Open Access Journals (Sweden)

    Alessandra Zappa

    2008-03-01

    Full Text Available Objective. During the 2004/2005 influenza season an active virological surveillance of influenza viruses and respiratory syncytial virus (RSV was carried out to monitor the epidemiologic trend of acute respiratory infections (ARI in the paediatric community. Materials and methods. 100 patients (51 males, 49 females; mean age: 19 months, either treated at the Emergency Unit or hospitalized in the Pediatric Unit of “San Carlo Borromeo Hospital” (Milan, reporting symptoms related to ARI were enrolled. Pharyngeal swabs were collected for virological investigation by: 1 multiplexnested- PCR for the simultaneous identification of both influenza A and B viruses and RSV; 2 multiplex-nested- PCR for the subtyping of influenza A viruses (H1 and H3. Results. 12% (12/100 subjects were infected with influenza A virus, 4% (4/100 with influenza B virus and 14 (14% with RSV. Of all the 12 influenza A positive samples 4 (33.3% belonged to subtype H1 and 8 (66.7% to subtype H3. Bronchiolitis and bronchitis episodes were significantly higher among RSV-infected subjects than among influenza- infected subjects (42.8% vs 6.2%; p<0.05 and 35.7% vs 6.2%; p<0.05, respectively. Pneumonia episodes occurred similarly both in influenza-infected children and in RSV-infected ones. Conclusions. During the 2004/2005 influenza season, influenza viruses and RSV were liable for high morbidity among paediatric subjects.The present study underlies the importance of planning an active surveillance of respiratory viral infections among paediatric cases requiring hospitalization due to ARI.A thorough analysis of target population features, of viruses antigenic properties and seasonality will be decisive in the evaluation of each clinical event.

  19. Murine leukemia virus (MLV replication monitored with fluorescent proteins

    Directory of Open Access Journals (Sweden)

    Bittner Alexandra

    2004-12-01

    Full Text Available Abstract Background Cancer gene therapy will benefit from vectors that are able to replicate in tumor tissue and cause a bystander effect. Replication-competent murine leukemia virus (MLV has been described to have potential as cancer therapeutics, however, MLV infection does not cause a cytopathic effect in the infected cell and viral replication can only be studied by immunostaining or measurement of reverse transcriptase activity. Results We inserted the coding sequences for green fluorescent protein (GFP into the proline-rich region (PRR of the ecotropic envelope protein (Env and were able to fluorescently label MLV. This allowed us to directly monitor viral replication and attachment to target cells by flow cytometry. We used this method to study viral replication of recombinant MLVs and split viral genomes, which were generated by replacement of the MLV env gene with the red fluorescent protein (RFP and separately cloning GFP-Env into a retroviral vector. Co-transfection of both plasmids into target cells resulted in the generation of semi-replicative vectors, and the two color labeling allowed to determine the distribution of the individual genomes in the target cells and was indicative for the occurrence of recombination events. Conclusions Fluorescently labeled MLVs are excellent tools for the study of factors that influence viral replication and can be used to optimize MLV-based replication-competent viruses or vectors for gene therapy.

  20. Vaccinia virus as a subhelper for AAV replication and packaging

    Directory of Open Access Journals (Sweden)

    Andrea R Moore

    Full Text Available Adeno-associated virus (AAV has been widely used as a gene therapy vector to treat a variety of disorders. While these vectors are increasingly popular and successful in the clinic, there is still much to learn about the viruses. Understanding the biology of these viruses is essential in engineering better vectors and generating vectors more efficiently for large-scale use. AAV requires a helper for production and replication making this aspect of the viral life cycle crucial. Vaccinia virus (VV has been widely cited as a helper virus for AAV. However, to date, there are no detailed analyses of its helper function. Here, the helper role of VV was studied in detail. In contrast to common belief, we demonstrated that VV was not a sufficient helper virus for AAV replication. Vaccinia failed to produce rAAV and activate AAV promoters. While this virus could not support rAAV production, Vaccinia could initiate AAV replication and packaging when AAV promoter activation is not necessary. This activity is due to the ability of Vaccinia-driven Rep78 to transcribe in the cytoplasm and subsequently translate in the nucleus and undergo typical functions in the AAV life cycle. As such, VV is subhelper for AAV compared to complete helper functions of adenovirus.

  1. Cyclophilin B facilitates the replication of Orf virus.

    Science.gov (United States)

    Zhao, Kui; Li, Jida; He, Wenqi; Song, Deguang; Zhang, Ximu; Zhang, Di; Zhou, Yanlong; Gao, Feng

    2017-06-15

    Viruses interact with host cellular factors to construct a more favourable environment for their efficient replication. Expression of cyclophilin B (CypB), a cellular peptidyl-prolyl cis-trans isomerase (PPIase), was found to be significantly up-regulated. Recently, a number of studies have shown that CypB is important in the replication of several viruses, including Japanese encephalitis virus (JEV), hepatitis C virus (HCV) and human papillomavirus type 16 (HPV 16). However, the function of cellular CypB in ORFV replication has not yet been explored. Suppression subtractive hybridization (SSH) technique was applied to identify genes differentially expressed in the ORFV-infected MDBK cells at an early phase of infection. Cellular CypB was confirmed to be significantly up-regulated by quantitative reverse transcription-PCR (qRT-PCR) analysis and Western blotting. The role of CypB in ORFV infection was further determined using Cyclosporin A (CsA) and RNA interference (RNAi). Effect of CypB gene silencing on ORFV replication by 50% tissue culture infectious dose (TCID 50 ) assay and qRT-PCR detection. In the present study, CypB was found to be significantly up-regulated in the ORFV-infected MDBK cells at an early phase of infection. Cyclosporin A (CsA) exhibited suppressive effects on ORFV replication through the inhibition of CypB. Silencing of CypB gene inhibited the replication of ORFV in MDBK cells. In conclusion, these data suggest that CypB is critical for the efficient replication of the ORFV genome. Cellular CypB was confirmed to be significantly up-regulated in the ORFV-infected MDBK cells at an early phase of infection, which could effectively facilitate the replication of ORFV.

  2. Dengue virus replicates and accumulates in Aedes aegypti salivary glands

    Energy Technology Data Exchange (ETDEWEB)

    Raquin, Vincent, E-mail: vincent.raquin@univ-lyon1.fr [Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, 75015 Paris (France); Centre National de la Recherche Scientifique, Unité de Recherche Associée 3012, 75015 Paris (France); Lambrechts, Louis, E-mail: louis.lambrechts@pasteur.fr [Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, 75015 Paris (France); Centre National de la Recherche Scientifique, Unité de Recherche Associée 3012, 75015 Paris (France)

    2017-07-15

    Dengue virus (DENV) is an RNA virus transmitted among humans by mosquito vectors, mainly Aedes aegypti. DENV transmission requires viral dissemination from the mosquito midgut to the salivary glands. During this process the virus undergoes several population bottlenecks, which are stochastic reductions in population size that restrict intra-host viral genetic diversity and limit the efficiency of natural selection. Despite the implications for virus transmission and evolution, DENV replication in salivary glands has not been directly demonstrated. Here, we used a strand-specific quantitative RT-PCR assay to demonstrate that negative-strand DENV RNA is produced in Ae. aegypti salivary glands, providing conclusive evidence that viral replication occurs in this tissue. Furthermore, we showed that the concentration of DENV genomic RNA in salivary glands increases significantly over time, indicating that active replication likely replenishes DENV genetic diversity prior to transmission. These findings improve our understanding of the biological determinants of DENV fitness and evolution. - Highlights: •Strand-specific RT-qPCR allows accurate quantification of DENV (-) RNA in mosquito tissues. •Detection of DENV (-) RNA in salivary glands provides evidence of viral replication in this tissue. •Viral replication in salivary glands likely replenishes DENV genetic diversity prior to transmission.

  3. Dengue virus replicates and accumulates in Aedes aegypti salivary glands

    International Nuclear Information System (INIS)

    Raquin, Vincent; Lambrechts, Louis

    2017-01-01

    Dengue virus (DENV) is an RNA virus transmitted among humans by mosquito vectors, mainly Aedes aegypti. DENV transmission requires viral dissemination from the mosquito midgut to the salivary glands. During this process the virus undergoes several population bottlenecks, which are stochastic reductions in population size that restrict intra-host viral genetic diversity and limit the efficiency of natural selection. Despite the implications for virus transmission and evolution, DENV replication in salivary glands has not been directly demonstrated. Here, we used a strand-specific quantitative RT-PCR assay to demonstrate that negative-strand DENV RNA is produced in Ae. aegypti salivary glands, providing conclusive evidence that viral replication occurs in this tissue. Furthermore, we showed that the concentration of DENV genomic RNA in salivary glands increases significantly over time, indicating that active replication likely replenishes DENV genetic diversity prior to transmission. These findings improve our understanding of the biological determinants of DENV fitness and evolution. - Highlights: •Strand-specific RT-qPCR allows accurate quantification of DENV (-) RNA in mosquito tissues. •Detection of DENV (-) RNA in salivary glands provides evidence of viral replication in this tissue. •Viral replication in salivary glands likely replenishes DENV genetic diversity prior to transmission.

  4. Characterization of oligosaccharide structures on a chimeric respiratory syncytial virus protein expressed in insect cell line Sf9

    International Nuclear Information System (INIS)

    Wathen, M.W.; Aeed, P.A.; Elhammer, A.P.

    1991-01-01

    The oligosaccharide structures added to a chimeric protein (FG) composed of the extracellular domains of respiratory syncytial virus F and G proteins, expressed in the insect cell line Sf9, were investigated. Cells were labeled in vivo with [ 3 H]glucosamine and infected wit a recombinant baculovirus containing the FG gene. The secreted chimeric protein was isolated by immunoprecipitation and subjected to oligosaccharide analysis. The FG protein contains two types of O-linked oligosaccharides: GalNAc and Galβ1-3GalNAc constituting 17 and 66% of the total number of structures respectively. Only one type of N-linked oligosaccharide, constituting the remaining 17% of the structures on FG, was detected: a trimannosyl core structure with a fucose residue linked α1-6 to the asparagine-linked N-acetylglucosamine

  5. A multi-tiered time-series modelling approach to forecasting respiratory syncytial virus incidence at the local level.

    Science.gov (United States)

    Spaeder, M C; Fackler, J C

    2012-04-01

    Respiratory syncytial virus (RSV) is the most common cause of documented viral respiratory infections, and the leading cause of hospitalization, in young children. We performed a retrospective time-series analysis of all patients aged Forecasting models of weekly RSV incidence for the local community, inpatient paediatric hospital and paediatric intensive-care unit (PICU) were created. Ninety-five percent confidence intervals calculated around our models' 2-week forecasts were accurate to ±9·3, ±7·5 and ±1·5 cases/week for the local community, inpatient hospital and PICU, respectively. Our results suggest that time-series models may be useful tools in forecasting the burden of RSV infection at the local and institutional levels, helping communities and institutions to optimize distribution of resources based on the changing burden and severity of illness in their respective communities.

  6. Increase of CTGF mRNA expression by respiratory syncytial virus infection is abrogated by caffeine in lung epithelial cells.

    Science.gov (United States)

    Kunzmann, Steffen; Krempl, Christine; Seidenspinner, Silvia; Glaser, Kirsten; Speer, Christian P; Fehrholz, Markus

    2018-04-16

    Respiratory syncytial virus (RSV) is a leading cause of severe lower respiratory tract infection in early childhood. Underlying pathomechanisms of elevated pulmonary morbidity in later infancy are largely unknown. We found that RSV-infected H441 cells showed increased mRNA expression of connective tissue growth factor (CTGF), a key factor in airway remodeling. Additional dexamethasone treatment led to further elevated mRNA levels, indicating additive effects. Caffeine treatment prevented RSV-mediated increase of CTGF mRNA. RSV may be involved in airway remodeling processes by increasing CTGF mRNA expression. Caffeine might abrogate these negative effects and thereby help to restore lung homeostasis. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  7. Functional analysis of replication determinantsin classical swine fever virus

    DEFF Research Database (Denmark)

    Hadsbjerg, Johanne

    and animal pathogens should facilitate finding new approaches for efficient disease control. The principal aim of this thesis is to characterise determinants involved in the replication of classical swine fever virus (CSFV). Classical swine fever is a highly contagious virus disease of domestic pigs and wild...... in cell culture. Knowledge of these sequence variations and putative long-range interactions will provide valuable insights into mechanisms underlying virustranslation and replication. In manuscript 3, a selection marker has been inserted into a CSFV-based replicon making it suitable for screening...

  8. Infection and Replication of Influenza Virus at the Ocular Surface.

    Science.gov (United States)

    Creager, Hannah M; Kumar, Amrita; Zeng, Hui; Maines, Taronna R; Tumpey, Terrence M; Belser, Jessica A

    2018-04-01

    Although influenza viruses typically cause respiratory tract disease, some viruses, particularly those with an H7 hemagglutinin, have been isolated from the eyes of conjunctivitis cases. Previous work has shown that isolates of multiple subtypes from both ocular and respiratory infections are capable of replication in human ex vivo ocular tissues and corneal or conjunctival cell monolayers, leaving the determinants of ocular tropism unclear. Here, we evaluated the effect of several variables on tropism for ocular cells cultured in vitro and examined the potential effect of the tear film on viral infectivity. All viruses tested were able to replicate in primary human corneal epithelial cell monolayers subjected to aerosol inoculation. The temperature at which cells were cultured postinoculation minimally affected infectivity. Replication efficiency, in contrast, was reduced at 33°C relative to that at 37°C, and this effect was slightly greater for the conjunctivitis isolates than for the respiratory ones. With the exception of a seasonal H3N2 virus, the subset of viruses studied in multilayer corneal tissue constructs also replicated productively after either aerosol or liquid inoculation. Human tears significantly inhibited the hemagglutination of both ocular and nonocular isolates, but the effect on viral infectivity was more variable, with tears reducing the infectivity of nonocular isolates more than ocular isolates. These data suggest that most influenza viruses may be capable of establishing infection if they reach the surface of ocular cells but that this is more likely for ocular-tropic viruses, as they are better able to maintain their infectivity during passage through the tear film. IMPORTANCE The potential spread of zoonotic influenza viruses to humans represents an important threat to public health. Unfortunately, despite the importance of cellular and tissue tropism to pathogenesis, determinants of influenza virus tropism have yet to be fully

  9. Inhibition of virus replication by RNA interference

    NARCIS (Netherlands)

    Haasnoot, P. C. Joost; Cupac, Daniel; Berkhout, Ben

    2003-01-01

    RNA interference (RNAi) is a sequence-specific gene-silencing mechanism in eukaryotes, which is believed to function as a defence against viruses and transposons. Since its discovery, RNAi has been developed into a widely used technique for generating genetic knock-outs and for studying gene

  10. Pyrimidine dimers block simian virus 40 replication forks

    International Nuclear Information System (INIS)

    Berger, C.A.; Edenberg, H.J.

    1986-01-01

    UV light produces lesions, predominantly pyrimidine dimers, which inhibit DNA replication in mammalian cells. The mechanism of inhibition is controversial: is synthesis of a daughter strand halted at a lesion while the replication fork moves on and reinitiates downstream, or is fork progression itself blocked for some time at the site of a lesion? We directly addressed this question by using electron microscopy to examine the distances of replication forks from the origin in unirradiated and UV-irradiated simian virus 40 chromosomes. If UV lesions block replication fork progression, the forks should be asymmetrically located in a large fraction of the irradiated molecules; if replication forks move rapidly past lesions, the forks should be symmetrically located. A large fraction of the simian virus 40 replication forks in irradiated molecules were asymmetrically located, demonstrating that UV lesions present at the frequency of pyrimidine dimers block replication forks. As a mechanism for this fork blockage, we propose that polymerization of the leading strand makes a significant contribution to the energetics of fork movement, so any lesion in the template for the leading strand which blocks polymerization should also block fork movement

  11. Incidence and Risk Factors for Respiratory Syncytial Virus and Human Metapneumovirus Infections among Children in the Remote Highlands of Peru

    Science.gov (United States)

    Wu, Andrew; Budge, Philip J.; Williams, John; Griffin, Marie R.; Edwards, Kathryn M.; Johnson, Monika; Zhu, Yuwei; Hartinger, Stella; Verastegui, Hector; Gil, Ana I.; Lanata, Claudio F.; Grijalva, Carlos G.

    2015-01-01

    Introduction The disease burden and risk factors for respiratory syncytial virus (RSV) and human metapneumovirus (MPV) infections among children living in remote, rural areas remain unclear. Materials and Methods We conducted a prospective, household-based cohort study of children aged factors for RSV detection included younger age (RR 1.02, 95% CI: 1.00-1.03), the presence of a smoker in the house (RR 1.63, 95% CI: 1.12-2.38), residing at higher altitudes (RR 1.93, 95% CI: 1.25-3.00 for 2nd compared to 1st quartile residents; RR 1.98, 95% CI: 1.26-3.13 for 3rd compared to 1st quartile residents). Having an unemployed household head was significantly associated with MPV risk (RR 2.11, 95% CI: 1.12-4.01). Conclusion In rural high altitude communities in Peru, childhood ARI due to RSV or MPV were common and associated with higher morbidity than ARI due to other viruses or with no viral detections. The risk factors identified in this study may be considered for interventional studies to control infections by these viruses among young children from developing countries. PMID:26107630

  12. Structural and Nonstructural Viral Proteins Are Targets of T-Helper Immune Response against Human Respiratory Syncytial Virus.

    Science.gov (United States)

    Lorente, Elena; Barriga, Alejandro; Barnea, Eilon; Mir, Carmen; Gebe, John A; Admon, Arie; López, Daniel

    2016-06-01

    Proper antiviral humoral and cellular immune responses require previous recognition of viral antigenic peptides that are bound to HLA class II molecules, which are exposed on the surface of antigen-presenting cells. The helper immune response is critical for the control and the clearance of human respiratory syncytial virus (HRSV) infection, a virus with severe health risk in infected pediatric, immunocompromised, and elderly populations. In this study, using a mass spectrometry analysis of complex HLA class II-bound peptide pools that were isolated from large amounts of HRSV-infected cells, 19 naturally processed HLA-DR ligands, most of them included in a complex nested set of peptides, were identified. Both the immunoprevalence and the immunodominance of the HLA class II response to HRSV were focused on one nonstructural (NS1) and two structural (matrix and mainly fusion) proteins of the infective virus. These findings have clear implications for analysis of the helper immune response as well as for antiviral vaccine design. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Modeling Ebola Virus Genome Replication and Transcription with Minigenome Systems.

    Science.gov (United States)

    Cressey, Tessa; Brauburger, Kristina; Mühlberger, Elke

    2017-01-01

    In this chapter, we describe the minigenome system for Ebola virus (EBOV), which reconstitutes EBOV polymerase activity in cells and can be used to model viral genome replication and transcription. This protocol comprises all steps including cell culture, plasmid preparation, transfection, and luciferase reporter assay readout.

  14. A dynamic model for in vivo virus replication

    Energy Technology Data Exchange (ETDEWEB)

    MacCarthy, J.E.; Kozak, J.J.

    1980-01-01

    In this paper a dynamic model of in vivo virus replication is presented. Kinetic equations are formulated to describe the overall process of replication and then analyzed using a ''synergetic'' approach. First the importance of a rate-limiting substrate is taken explicitly into account, and secondly the coupling between the processes considered (translation, replication and assembly) is strictly preserved; the analysis itself is carried out in the linear regime. The problems of defective-particle infections, standard-virus infections, inhibition of cellular synthesis, and the case of co-infected cells are treated. The various parameters of the model (initial cellular concentrations, rate constants) are specified using existing experimental data and the full (numerical) consequences of the model are explored in detail. The simple model developed is able to account qualitatively, and occasionally quantitatively, for the behavior observed experimentally for each of the problems cited above.

  15. Distinct Contributions of Autophagy Receptors in Measles Virus Replication.

    Science.gov (United States)

    Petkova, Denitsa S; Verlhac, Pauline; Rozières, Aurore; Baguet, Joël; Claviere, Mathieu; Kretz-Remy, Carole; Mahieux, Renaud; Viret, Christophe; Faure, Mathias

    2017-05-22

    Autophagy is a potent cell autonomous defense mechanism that engages the lysosomal pathway to fight intracellular pathogens. Several autophagy receptors can recognize invading pathogens in order to target them towards autophagy for their degradation after the fusion of pathogen-containing autophagosomes with lysosomes. However, numerous intracellular pathogens can avoid or exploit autophagy, among which is measles virus (MeV). This virus induces a complete autophagy flux, which is required to improve viral replication. We therefore asked how measles virus interferes with autophagy receptors during the course of infection. We report that in addition to NDP52/CALCOCO₂ and OPTINEURIN/OPTN, another autophagy receptor, namely T6BP/TAXIBP1, also regulates the maturation of autophagosomes by promoting their fusion with lysosomes, independently of any infection. Surprisingly, only two of these receptors, NDP52 and T6BP, impacted measles virus replication, although independently, and possibly through physical interaction with MeV proteins. Thus, our results suggest that a restricted set of autophagosomes is selectively exploited by measles virus to replicate in the course of infection.

  16. Diverse Effects of Cyclosporine on Hepatitis C Virus Strain Replication

    Science.gov (United States)

    Ishii, Naoto; Watashi, Koichi; Hishiki, Takayuki; Goto, Kaku; Inoue, Daisuke; Hijikata, Makoto; Wakita, Takaji; Kato, Nobuyuki; Shimotohno, Kunitada

    2006-01-01

    Recently, a production system for infectious particles of hepatitis C virus (HCV) utilizing the genotype 2a JFH1 strain has been developed. This strain has a high capacity for replication in the cells. Cyclosporine (CsA) has a suppressive effect on HCV replication. In this report, we characterize the anti-HCV effect of CsA. We observe that the presence of viral structural proteins does not influence the anti-HCV activity of CsA. Among HCV strains, the replication of genotype 1b replicons was strongly suppressed by treatment with CsA. In contrast, JFH1 replication was less sensitive to CsA and its analog, NIM811. Replication of JFH1 did not require the cellular replication cofactor, cyclophilin B (CyPB). CyPB stimulated the RNA binding activity of NS5B in the genotype 1b replicon but not the genotype 2a JFH1 strain. These findings provide an insight into the mechanisms of diversity governing virus-cell interactions and in the sensitivity of these strains to antiviral agents. PMID:16611911

  17. Hepatitis A Virus Genome Organization and Replication Strategy.

    Science.gov (United States)

    McKnight, Kevin L; Lemon, Stanley M

    2018-04-02

    Hepatitis A virus (HAV) is a positive-strand RNA virus classified in the genus Hepatovirus of the family Picornaviridae It is an ancient virus with a long evolutionary history and multiple features of its capsid structure, genome organization, and replication cycle that distinguish it from other mammalian picornaviruses. HAV proteins are produced by cap-independent translation of a single, long open reading frame under direction of an inefficient, upstream internal ribosome entry site (IRES). Genome replication occurs slowly and is noncytopathic, with transcription likely primed by a uridylated protein primer as in other picornaviruses. Newly produced quasi-enveloped virions (eHAV) are released from cells in a nonlytic fashion in a unique process mediated by interactions of capsid proteins with components of the host cell endosomal sorting complexes required for transport (ESCRT) system. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  18. Analysis of biennial outbreak pattern of respiratory syncytial virus according to subtype (A and B) in the Zagreb region.

    Science.gov (United States)

    Mlinaric-Galinovic, Gordana; Tabain, Irena; Kukovec, Tamara; Vojnovic, Gordana; Bozikov, Jadranka; Bogovic-Cepin, Jasna; Ivkovic-Jurekovic, Irena; Knezovic, Ivica; Tesovic, Goran; Welliver, Robert C

    2012-06-01

    The epidemic pattern of respiratory syncytial virus (RSV) in Croatia is biennial. In order to determine if the circulation of different RSV subtypes affects the outbreak cycle, the aim of the present study was to analyze the epidemic pattern of RSV in children in Croatia (Zagreb region) over a period of 3 consecutive years. The study group consisted of 696 inpatients, aged 0-5 years, who were hospitalized with acute respiratory tract infections caused by RSV, in Zagreb, in the period 1 January 2006-31 December 2008. The virus was identified in nasopharyngeal secretions using direct immunofluorescence. The virus subtype was determined on real-time polymerase chain reaction. Of 696 RSV infections identified in children, subtype A virus caused 374 infections, and subtype B, 318. Four patients had a dual RSV infection (subtypes A and B). The period of study was characterized by four epidemic waves of RSV infections: the first, smaller, in the spring of 2006; the second, larger, in December 2006/January 2007; the third in spring 2008, followed by a fourth outbreak beginning in November of 2008. The biennial virus cycles were persistent although the predominant RSV subtype in the first two epidemic waves was subtype B, and in the second two it was subtype A. Over a 3 year period of observation, the biennial RSV cycle in Croatia cannot be explained by a difference in the predominant circulating subtype of RSV. Other unknown factors account for the biennial cycle of RSV epidemics in Croatia. © 2011 The Authors. Pediatrics International © 2011 Japan Pediatric Society.

  19. Prospective and retrospective evaluation of the Cepheid Xpert® Flu/RSV XC assay for rapid detection of influenza A, influenza B, and respiratory syncytial virus.

    Science.gov (United States)

    Salez, Nicolas; Nougairede, Antoine; Ninove, Laetitia; Zandotti, Christine; de Lamballerie, Xavier; Charrel, Remi N

    2015-04-01

    A total of 281 clinical specimens (nasal swabs and nasopharyngeal aspirates) were tested with the Xpert® Flu/RSV XC. The results were compared to those obtained with the real-time retro transcriptase-polymerase chain reaction assays routinely used in our laboratory. The Xpert® Flu/RSV XC showed sensitivity/specificity of 97.8%/100% and 97.9%/100% for flu and respiratory syncytial virus, respectively. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Virucidal activities of medium- and long-chain fatty alcohols and lipids against respiratory syncytial virus and parainfluenza virus type 2: comparison at different pH levels.

    Science.gov (United States)

    Hilmarsson, H; Traustason, B S; Kristmundsdóttir, T; Thormar, H

    2007-01-01

    Recent studies have shown that some lipids and fatty alcohols have microbicidal activities against a broad variety of pathogens. In this study, virucidal activities of fatty acids, monoglycerides and fatty alcohols were tested against respiratory syncytial virus (RSV) and human parainfluenza virus type 2 (HPIV2) at different concentrations, times and pH levels. The most active compounds were mixed with milk products and fruit juices and the mixtures tested for virucidal effects. The aim was to determine which compounds are the most active against these respiratory viruses and could possibly be used in pharmaceutical formulations or as additives to milk products or juice. Several compounds caused a significant inactivation of virus, and there was generally a good agreement between the activities against RSV and parainfluenza virus. By changing the pH from 7 to 4.2, the virucidal activities of some of the compounds were greatly increased, i.e., they inactivated virus in a shorter time and at lower concentrations. The most active compound tested was 1-monoglyceride of capric acid, monocaprin, which also showed activity against influenza A virus and significant virucidal activities after addition to milk products and fruit juices, even at a concentration as low as 0.06-0.12%. The significant virucidal activities of fatty alcohols and lipids on RSV and parainfluenza virus demonstrated in this in vitro study raise the question of the feasibility of using such compounds as ingredients in pharmaceutical dosage forms against respiratory infections caused by these viruses, and possibly other paramyxo- and myxoviruses.

  1. Molecular Characterization of Respiratory Syncytial Virus in Children with Repeated Infections with Subgroup B in the Philippines.

    Science.gov (United States)

    Okamoto, Michiko; Dapat, Clyde P; Sandagon, Ann Marie D; Batangan-Nacion, Leilanie P; Lirio, Irene C; Tamaki, Raita; Saito, Mayuko; Saito-Obata, Mariko; Lupisan, Socorro P; Oshitani, Hitoshi

    2018-05-02

    Human respiratory syncytial virus (RSV) is the leading cause of severe acute respiratory infection in infants and young children, which is characterized by repeated infections. However, the role of amino acid substitutions in repeated infections remains unclear. Hence, this study aimed to elucidate the genetic characteristics of RSV in children with repeated infections using molecular analyses of F and G genes. We conducted a cohort study for children younger than 5 years in the Philippines. We collected nasopharyngeal swabs from children with acute respiratory symptoms and compared F and G sequences between prior and subsequent RSV infections. We examined 1,802 children from May 2014 to January 2016 and collected 3,471 samples. Repeated infections were observed in 25 children, including 4 with homologous RSV-B reinfections. Viruses from the 4 pairs of homologous reinfections had amino acid substitutions in the G protein mostly at O-glycosylation sites, whereas changes in the F protein were identified at antigenic sites V (L173S) and θ (Q209K), considered essential epitopes for the prefusion conformation of the F protein. Amino acid substitutions in G and F proteins of RSV-B might have led to antigenic changes, potentially contributing to homologous reinfections observed in this study.

  2. Modulation of Host Immunity by Human Respiratory Syncytial Virus Virulence Factors: A Synergic Inhibition of Both Innate and Adaptive Immunity

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    Gisela Canedo-Marroquín

    2017-08-01

    Full Text Available The Human Respiratory Syncytial Virus (hRSV is a major cause of acute lower respiratory tract infections (ARTIs and high rates of hospitalizations in children and in the elderly worldwide. Symptoms of hRSV infection include bronchiolitis and pneumonia. The lung pathology observed during hRSV infection is due in part to an exacerbated host immune response, characterized by immune cell infiltration to the lungs. HRSV is an enveloped virus, a member of the Pneumoviridae family, with a non-segmented genome and negative polarity-single RNA that contains 10 genes encoding for 11 proteins. These include the Fusion protein (F, the Glycoprotein (G, and the Small Hydrophobic (SH protein, which are located on the virus surface. In addition, the Nucleoprotein (N, Phosphoprotein (P large polymerase protein (L part of the RNA-dependent RNA polymerase complex, the M2-1 protein as a transcription elongation factor, the M2-2 protein as a regulator of viral transcription and (M protein all of which locate inside the virion. Apart from the structural proteins, the hRSV genome encodes for the non-structural 1 and 2 proteins (NS1 and NS2. HRSV has developed different strategies to evade the host immunity by means of the function of some of these proteins that work as virulence factors to improve the infection in the lung tissue. Also, hRSV NS-1 and NS-2 proteins have been shown to inhibit the activation of the type I interferon response. Furthermore, the hRSV nucleoprotein has been shown to inhibit the immunological synapsis between the dendritic cells and T cells during infection, resulting in an inefficient T cell activation. Here, we discuss the hRSV virulence factors and the host immunological features raised during infection with this virus.

  3. DNA intercalator stimulates influenza transcription and virus replication

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    Poon Leo LM

    2011-03-01

    Full Text Available Abstract Influenza A virus uses its host transcription machinery to facilitate viral RNA synthesis, an event that is associated with cellular RNA polymerase II (RNAPII. In this study, various RNAPII transcription inhibitors were used to investigate the effect of RNAPII phosphorylation status on viral RNA transcription. A low concentration of DNA intercalators, such as actinomycin D (ActD, was found to stimulate viral polymerase activity and virus replication. This effect was not observed in cells treated with RNAPII kinase inhibitors. In addition, the loss of RNAPIIa in infected cells was due to the shift of nonphosphorylated RNAPII (RNAPIIa to hyperphosphorylated RNAPII (RNAPIIo.

  4. Replicative intermediates in UV-irradiated Simian virus 40

    International Nuclear Information System (INIS)

    Clark, J.M.; Hanawalt, P.C.

    1984-01-01

    The authors have used Simian virus 40 (SV40) as a probe to study the replication of UV-damaged DNA in mammalian cells. Viral DNA replication in infected monkey kidney cells was synchronized by incubating a mutant of SV40 (tsA58) temperature-sensitive for the initiation of DNA synthesis at the restrictive temperature and then adding aphidicolin to temporarily inhibit DNA synthesis at the permissive temperature while permitting pre-replicative events to occur. After removal of the drug, the infected cells were irradiated at 100 J/m 2 (254 nm) to produce 6-7 pyrimidine dimers per SV40 genome, and returned to the restrictive temperature to prevent reinitiation of replication from the SV40 origin. Replicative intermediates (RI) were labeled with [ 3 H]thymidine. The size distribution of daughter DNA strands in RI isolated shortly after irradiation was skewed towards lengths less than the interdimer spacing in parental DNA; this bias persisted for at least 1 h after irradiation, but disappeared within 3 h by which time the size of the newly-synthesized DNA exceeded the interdimer distance. Evidence was obtained for the generation at late times after irradiation, of Form I molecules in which the daughter DNA strand contain dimers. Thus DNA strand exchange as well as trans-dimer synthesis may be involved in the generation of supercoiled Form I DNA from 0V-damaged SV40 replicative intermediates. (Auth.)

  5. Cathepsin B & L are not required for ebola virus replication.

    Science.gov (United States)

    Marzi, Andrea; Reinheckel, Thomas; Feldmann, Heinz

    2012-01-01

    Ebola virus (EBOV), family Filoviridae, emerged in 1976 on the African continent. Since then it caused several outbreaks of viral hemorrhagic fever in humans with case fatality rates up to 90% and remains a serious Public Health concern and biothreat pathogen. The most pathogenic and best-studied species is Zaire ebolavirus (ZEBOV). EBOV encodes one viral surface glycoprotein (GP), which is essential for replication, a determinant of pathogenicity and an important immunogen. GP mediates viral entry through interaction with cellular surface molecules, which results in the uptake of virus particles via macropinocytosis. Later in this pathway endosomal acidification activates the cysteine proteases Cathepsin B and L (CatB, CatL), which have been shown to cleave ZEBOV-GP leading to subsequent exposure of the putative receptor-binding and fusion domain and productive infection. We studied the effect of CatB and CatL on in vitro and in vivo replication of EBOV. Similar to previous findings, our results show an effect of CatB, but not CatL, on ZEBOV entry into cultured cells. Interestingly, cell entry by other EBOV species (Bundibugyo, Côte d'Ivoire, Reston and Sudan ebolavirus) was independent of CatB or CatL as was EBOV replication in general. To investigate whether CatB and CatL have a role in vivo during infection, we utilized the mouse model for ZEBOV. Wild-type (control), catB(-/-) and catL(-/-) mice were equally susceptible to lethal challenge with mouse-adapted ZEBOV with no difference in virus replication and time to death. In conclusion, our results show that CatB and CatL activity is not required for EBOV replication. Furthermore, EBOV glycoprotein cleavage seems to be mediated by an array of proteases making targeted therapeutic approaches difficult.

  6. Cathepsin B & L are not required for ebola virus replication.

    Directory of Open Access Journals (Sweden)

    Andrea Marzi

    Full Text Available Ebola virus (EBOV, family Filoviridae, emerged in 1976 on the African continent. Since then it caused several outbreaks of viral hemorrhagic fever in humans with case fatality rates up to 90% and remains a serious Public Health concern and biothreat pathogen. The most pathogenic and best-studied species is Zaire ebolavirus (ZEBOV. EBOV encodes one viral surface glycoprotein (GP, which is essential for replication, a determinant of pathogenicity and an important immunogen. GP mediates viral entry through interaction with cellular surface molecules, which results in the uptake of virus particles via macropinocytosis. Later in this pathway endosomal acidification activates the cysteine proteases Cathepsin B and L (CatB, CatL, which have been shown to cleave ZEBOV-GP leading to subsequent exposure of the putative receptor-binding and fusion domain and productive infection. We studied the effect of CatB and CatL on in vitro and in vivo replication of EBOV. Similar to previous findings, our results show an effect of CatB, but not CatL, on ZEBOV entry into cultured cells. Interestingly, cell entry by other EBOV species (Bundibugyo, Côte d'Ivoire, Reston and Sudan ebolavirus was independent of CatB or CatL as was EBOV replication in general. To investigate whether CatB and CatL have a role in vivo during infection, we utilized the mouse model for ZEBOV. Wild-type (control, catB(-/- and catL(-/- mice were equally susceptible to lethal challenge with mouse-adapted ZEBOV with no difference in virus replication and time to death. In conclusion, our results show that CatB and CatL activity is not required for EBOV replication. Furthermore, EBOV glycoprotein cleavage seems to be mediated by an array of proteases making targeted therapeutic approaches difficult.

  7. Design and characterization of epitope-scaffold immunogens that present the motavizumab epitope from respiratory syncytial virus.

    Science.gov (United States)

    McLellan, Jason S; Correia, Bruno E; Chen, Man; Yang, Yongping; Graham, Barney S; Schief, William R; Kwong, Peter D

    2011-06-24

    Respiratory syncytial virus (RSV) is a major cause of respiratory tract infections in infants, but an effective vaccine has not yet been developed. An ideal vaccine would elicit protective antibodies while avoiding virus-specific T-cell responses, which have been implicated in vaccine-enhanced disease with previous RSV vaccines. We propose that heterologous proteins designed to present RSV-neutralizing antibody epitopes and to elicit cognate antibodies have the potential to fulfill these vaccine requirements, as they can be fashioned to be free of viral T-cell epitopes. Here we present the design and characterization of three epitope-scaffolds that present the epitope of motavizumab, a potent neutralizing antibody that binds to a helix-loop-helix motif in the RSV fusion glycoprotein. Two of the epitope-scaffolds could be purified, and one epitope-scaffold based on a Staphylococcus aureus protein A domain bound motavizumab with kinetic and thermodynamic properties consistent with the free epitope-scaffold being stabilized in a conformation that closely resembled the motavizumab-bound state. This epitope-scaffold was well folded as assessed by circular dichroism and isothermal titration calorimetry, and its crystal structure (determined in complex with motavizumab to 1.9 Å resolution) was similar to the computationally designed model, with all hydrogen-bond interactions critical for binding to motavizumab preserved. Immunization of mice with this epitope-scaffold failed to elicit neutralizing antibodies but did elicit sera with F binding activity. The elicitation of F binding antibodies suggests that some of the design criteria for eliciting protective antibodies without virus-specific T-cell responses are being met, but additional optimization of these novel immunogens is required. Published by Elsevier Ltd.

  8. Respiratory syncytial virus--the unrecognised cause of health and economic burden among young children in Australia.

    Science.gov (United States)

    Ranmuthugala, Geetha; Brown, Laurie; Lidbury, Brett A

    2011-06-01

    Respiratory syncytial virus (RSV) presents very similar to influenza and is the principle cause of bronchiolitis in infants and young children worldwide. Yet, there is no systematic monitoring of RSV activity in Australia. This study uses existing published data sources to estimate incidence, hospitalisation rates, and associated costs of RSV among young children in Australia. Published reports from the Laboratory Virology and Serology Reporting Scheme, a passive voluntary surveillance system, and the National Hospital Morbidity Dataset were used to estimate RSV-related age-specific hospitalisation rates in New South Wales and Australia. These estimates and national USA estimates of RSV-related hospitalisation rates were applied to Australian population data to estimate RSV incidence in Australia. Direct economic burden was estimated by applying cost estimates used to derive economic cost associated with the influenza virus. The estimated RSV-related hospitalisation rates ranged from 2.2-4.5 per 1,000 among children less than 5 years of age to 8.7-17.4 per 1,000 among infants. Incidence ranged from 110.0-226.5 per 1,000 among the under five age group to 435.0-869.0 per 1,000 among infants. The total annual direct healthcare cost was estimated to be between $24 million and $50 million. Comparison with the health burdens attributed to the influenza virus and rotavirus suggests that the disease burden caused by RSV is potentially much higher. The limitations associated with using a passive surveillance system to estimate disease burden, and the need to explore further assessments and to monitor RSV activity are discussed.

  9. Monkey Viperin Restricts Porcine Reproductive and Respiratory Syndrome Virus Replication.

    Science.gov (United States)

    Fang, Jianyu; Wang, Haiyan; Bai, Juan; Zhang, Qiaoya; Li, Yufeng; Liu, Fei; Jiang, Ping

    2016-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen which causes huge economic damage globally in the swine industry. Current vaccination strategies provide only limited protection against PRRSV infection. Viperin is an interferon (IFN) stimulated protein that inhibits some virus infections via IFN-dependent or IFN-independent pathways. However, the role of viperin in PRRSV infection is not well understood. In this study, we cloned the full-length monkey viperin (mViperin) complementary DNA (cDNA) from IFN-α-treated African green monkey Marc-145 cells. It was found that the mViperin is up-regulated following PRRSV infection in Marc-145 cells along with elevated IRF-1 gene levels. IFN-α induced mViperin expression in a dose- and time-dependent manner and strongly inhibits PRRSV replication in Marc-145 cells. Overexpression of mViperin suppresses PRRSV replication by blocking the early steps of PRRSV entry and genome replication and translation but not inhibiting assembly and release. And mViperin co-localized with PRRSV GP5 and N protein, but only interacted with N protein in distinct cytoplasmic loci. Furthermore, it was found that the 13-16 amino acids of mViperin were essential for inhibiting PRRSV replication, by disrupting the distribution of mViperin protein from the granular distribution to a homogeneous distribution in the cytoplasm. These results could be helpful in the future development of novel antiviral therapies against PRRSV infection.

  10. Inhibition of herpes simplex virus replication by tobacco extracts.

    Science.gov (United States)

    Hirsch, J M; Svennerholm, B; Vahlne, A

    1984-05-01

    Herpes simplex virus type 1 (HSV-1) has been associated with the genesis of leukoplakias, epithelial atypia, and oral cancer. Tobacco habits, such as snuff dipping, are also definitely correlated with this type of lesion. The normal cytolytic HSV-1 infection can, after in vitro inactivation, transform cells. Extracts of snuff were prepared and assayed for their ability to inhibit HSV-1 replication. Plaque formation assays of HSV-1 in the presence of snuff extract showed that a reduced number of plaques was formed. Different batches of one brand of snuff were tested for inhibition of herpes simplex virus (HSV) production. More than 99% inhibition of 24-hr HSV production was obtained with undiluted batches. The 1:5 dilutions of snuff had an inhibitory effect of 85% and 1:25 dilutions, 39%. In agreement, the attachment of the virus to the host cell and penetration of the virus to the cell nuclei were found to be inhibited as was the synthesis of viral DNA. Nicotine had an inhibitory effect, while aromatic additions to snuff were found to have no major inhibitory effect on HSV replication. Snuff extracts were prepared from different brands of snuff reported to contain high and low quantities of tobacco-specific N-nitrosamines. Brands with reported high levels of tobacco-specific N-nitrosamines had significantly greater ability to inhibit HSV replication. In conclusion, this study has shown that extracts of snuff have inhibitory effects on the production of cytolytic HSV-1 infections. A chronic snuff dipper keeps tobacco in the mouth for the major part of the day. Thus, virus shed in the oral cavity in connection with a reactivated latent HSV-1 infection has great possibilities of being affected by snuff or derivatives of snuff. It is suggested that an interaction between tobacco products and HSV-1 might be involved in the development of dysplastic lesions in the oral cavity.

  11. Bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk - risk factors and spatial analysis.

    Science.gov (United States)

    Toftaker, Ingrid; Sanchez, Javier; Stokstad, Maria; Nødtvedt, Ane

    2016-10-01

    Bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCoV) are considered widespread among cattle in Norway and worldwide. This cross-sectional study was conducted based on antibody-ELISA of bulk tank milk (BTM) from 1347 herds in two neighboring counties in western Norway. The study aims were to determine the seroprevalence at herd level, to evaluate risk factors for BRSV and BCoV seropositivity, and to assess how these factors were associated with the spatial distribution of positive herds. The overall prevalence of BRSV and BCoV positive herds in the region was 46.2% and 72.2%, respectively. Isopleth maps of the prevalence risk distribution showed large differences in prevalence risk across the study area, with the highest prevalence in the northern region. Common risk factors of importance for both viruses were herd size, geographic location, and proximity to neighbors. Seropositivity for one virus was associated with increased odds of seropositivity for the other virus. Purchase of livestock was an additional risk factor for BCoV seropositivity, included in the model as in-degree, which was defined as the number of incoming movements from individual herds, through animal purchase, over a period of five years. Local dependence and the contribution of risk factors to this effect were assessed using the residuals from two logistic regression models for each virus. One model contained only the x- and y- coordinates as predictors, the other had all significant predictors included. Spatial clusters of high values of residuals were detected using the normal model of the spatial scan statistic and visualized on maps. Adjusting for the risk factors in the final models had different impact on the spatial clusters for the two viruses: For BRSV the number of clusters was reduced from six to four, for BCoV the number of clusters remained the same, however the log-likelihood ratios changed notably. This indicates that geographical differences in proximity to

  12. Co-immunization with virus-like particle and DNA vaccines induces protection against respiratory syncytial virus infection and bronchiolitis

    Science.gov (United States)

    Hwang, Hye Suk; Kwon, Young-Man; Lee, Jong Seok; Yoo, Si-Eun; Lee, Yu-Na; Ko, Eun-Ju; Kim, Min-Chul; Cho, Min-Kyoung; Lee, Young-Tae; Jung, Yu-Jin; Lee, Ji-Yun; Li, Jian Dong; Kang, Sang-Moo

    2014-01-01

    This study demonstrates that immunization with non-replicating virus-like particle (FFG VLP) containing RSV F and G glycoproteins together with RSV F DNA induced T helper type 1 antibody responses to RSV F similar to live RSV infection. Upon RSV challenge 21 weeks after immunization, FFG VLP vaccination induced protection against RSV infection as shown by clearance of lung viral loads, and the absence of eosinophil infiltrates, and did not cause lung pathology. In contrast, formalin-inactivated RSV (FI-RSV) vaccination showed significant pulmonary eosinophilia, severe mucus production, and extensive histopathology resulting in a hallmark of pulmonary pathology. Substantial lung pathology was also observed in mice with RSV re-infections. High levels of systemic and local inflammatory cytokine-secreting cells were induced in mice with FI-RSV but not with FFG VLP immunization after RSV challenge. Therefore, the results provide evidence that recombinant RSV FFG VLP vaccine can confer long-term protection against RSV without causing lung pathology. PMID:25110201

  13. Respiratory Syncytial Virus Nonstructural Proteins Upregulate SOCS1 and SOCS3 in the Different Manner from Endogenous IFN Signaling

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    Junwen Zheng

    2015-01-01

    Full Text Available Respiratory syncytial virus (RSV infection upregulates genes of the suppressor of cytokine signaling (SOCS family, which utilize a feedback loop to inhibit type I interferon dependent antiviral signaling pathway. Here, we reconstituted RSV nonstructural (NS protein expression plasmids (pNS1, pNS2, and pNS1/2 and tested whether NS1 or NS2 would trigger SOCS1 and SOCS3 protein expression. These NS proteins inhibited interferon- (IFN- α signaling through a mechanism involving the induction of SOCS1 and SOCS3, which appeared to be different from autocrine IFN dependent. NS1 induced both SOCS1 and SOCS3 upregulation, while NS2 only induced SOCS1 expression. The induced expression of SOCS1 and SOCS3 preceded endogenous IFN-signaling activation and inhibited the IFN-inducible antiviral response as well as chemokine induction. Treatments with INF-α and NS proteins both induced SOCS1 expression; however, they had opposing effects on IFN-α-dependent antiviral gene expression. Our results indicate that NS1 and NS2, which induce the expression of SOCS1 or SOCS3, might represent an independent pathway of stimulating endogenous IFN signaling.

  14. Positive selection results in frequent reversible amino acid replacements in the G protein gene of human respiratory syncytial virus.

    Science.gov (United States)

    Botosso, Viviane F; Zanotto, Paolo M de A; Ueda, Mirthes; Arruda, Eurico; Gilio, Alfredo E; Vieira, Sandra E; Stewien, Klaus E; Peret, Teresa C T; Jamal, Leda F; Pardini, Maria I de M C; Pinho, João R R; Massad, Eduardo; Sant'anna, Osvaldo A; Holmes, Eddie C; Durigon, Edison L

    2009-01-01

    Human respiratory syncytial virus (HRSV) is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a "flip-flop" phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites.

  15. Positive selection results in frequent reversible amino acid replacements in the G protein gene of human respiratory syncytial virus.

    Directory of Open Access Journals (Sweden)

    Viviane F Botosso

    2009-01-01

    Full Text Available Human respiratory syncytial virus (HRSV is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a "flip-flop" phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites.

  16. Outcome of the Respiratory Syncytial Virus related acute lower respiratory tract infection among hospitalized newborns: a prospective multicenter study.

    Science.gov (United States)

    Alan, Serdar; Erdeve, Omer; Cakir, Ufuk; Akduman, Hasan; Zenciroglu, Aysegul; Akcakus, Mustafa; Tunc, Turan; Gokmen, Zeynel; Ates, Can; Atasay, Begum; Arsan, Saadet

    2016-01-01

    To determine the incidence and outcomes of respiratory syncytial virus (RSV)-related acute lower respiratory tract infection (ALRI) including morbidity, nosocomial infection and mortality among newborn infants who were admitted to the neonatal intensive care units (NICUs). A multicenter, prospective study was conducted in newborns who were hospitalized with community acquired or nosocomial RSV infection in 44 NICUs throughout Turkey. Newborns with ALRI were screened for RSV infection by Respi-Strip®-test. Main outcome measures were the incidence of RSV-associated admissions in the NICUs and morbidity, mortality and epidemics results related to these admissions. The incidence of RSV infection was 1.24% (n: 250) and RSV infection constituted 19.6% of all ALRI hospitalizations, 226 newborns (90.4%) had community-acquired whereas 24 (9.6%) patients had nosocomial RSV infection in the NICUs. Of the 250 newborns, 171 (68.4%) were full-term infants, 183 (73.2%) had a BW >2500 g. RSV-related mortality rate was 1.2%. Four NICUs reported seven outbreaks on different months, which could be eliminated by palivizumab prophylaxis in one NICU. RSV-associated ALRI both in preterm and term infants accounts an important percent of hospitalizations in the season, and may threat other high-risk patients in the NICU.

  17. Independent lung ventilation in a newborn with asymmetric acute lung injury due to respiratory syncytial virus: a case report

    Directory of Open Access Journals (Sweden)

    Di Nardo Matteo

    2008-06-01

    Full Text Available Abstract Introduction Independent lung ventilation is a form of protective ventilation strategy used in adult asymmetric acute lung injury, where the application of conventional mechanical ventilation can produce ventilator-induced lung injury and ventilation-perfusion mismatch. Only a few experiences have been published on the use of independent lung ventilation in newborn patients. Case presentation We present a case of independent lung ventilation in a 16-day-old infant of 3.5 kg body weight who had an asymmetric lung injury due to respiratory syncytial virus bronchiolitis. We used independent lung ventilation applying conventional protective pressure controlled ventilation to the less-compromised lung, with a respiratory frequency proportional to the age of the patient, and a pressure controlled high-frequency ventilation to the atelectatic lung. This was done because a single tube conventional ventilation protective strategy would have exposed the less-compromised lung to a high mean airways pressure. The target of independent lung ventilation is to provide adequate gas exchange at a safe mean airways pressure level and to expand the atelectatic lung. Independent lung ventilation was accomplished for 24 hours. Daily chest radiograph and gas exchange were used to evaluate the efficacy of independent lung ventilation. Extubation was performed after 48 hours of conventional single-tube mechanical ventilation following independent lung ventilation. Conclusion This case report demonstrates the feasibility of independent lung ventilation with two separate tubes in neonates as a treatment of an asymmetric acute lung injury.

  18. A Preliminary Assessment of the Role of Ambient Nitric Oxide Exposure in Hospitalization with Respiratory Syncytial Virus Bronchiolitis

    Directory of Open Access Journals (Sweden)

    Nuredin I. Mohammed

    2016-06-01

    Full Text Available Some in vitro studies have indicated a possible link between respiratory syncytial virus (RSV infection and exposure to Nitric Oxide (NO. However, these studies used much higher NO concentrations than normally found in the ambient environment. This preliminary study explored whether an association was present with short-term exposure to NO in the environment. RSV-related admission data between November 2011 and February 2012 were obtained from Sheffield Children’s Hospital. The dates of admission were linked to contemporaneous ambient NO derived from sentinel air monitors. The case-crossover design was used to study the relationship between daily RSV admissions and NO, controlling for temperature and relative humidity. We found little evidence of association between daily RSV admission rates and exposure to ambient NO at different lags or average exposure across several lags. The findings should, however, be viewed with caution due to the low number of events observed during the time frame. It is possible that the apparent lack of association may be accounted for by the timing of the seasonal RSV epidemic in relation to peaks in NO concentrations. A larger study incorporating a wider range of RSV and NO peaks would determine whether said peaks enhanced the number of RSV hospitalizations in children.

  19. FACTORS DETERMINING THE HOSPITALISATION DURATION OF STAY IN CHILDREN WITH SEVERE RESPIRATORY SYNCYTIAL VIRUS (RSV INFECTION IN THE RUSSIAN FEDERATION

    Directory of Open Access Journals (Sweden)

    A.A. Baranov

    2011-01-01

    Full Text Available The epidemiologic data on RSV infection prevalence in the Russian Federation and its impact on respiratory morbidity in the pediatric population are limited. This article provides the analysis of results of a prospective, multicenter, observational cohort study. The study was conducted in 9 centers in the Russian Federation — in Moscow, St. Petersburg, and Tomsk. Children less than 2 years of age were included. It was found that during the season of high RSV morbidity RSV is found in 38 % of children hospitalized for lower respiratory tract infections; mean hospitalisation duration in children with severe RSV infection was over 1 week. Usually the duration of hospitalization was associated with disease severity and requirements for healthcare resources and oxygen supplementation. Moreover, in the Russian Federation the hospital length of stay in patients with RSV infection depended on the type of medical insurance. It was demonstrated that RSV infection caused severe respiratory failure in some infants less than 1 year of age and, therefore, was a substantial burden for the system of hospital medical care in the Russian Federation. Prophylaxis of severe RSV infection in high-risk groups of children during the might reduce the need for hospitalization. Key words: respiratory syncytial virus infection, bronchiolitis, risk factors, prophylaxis, epidemiology, children. (Pediatric pharmacology. — 2011; 8 (6: 61–66.

  20. Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

    Directory of Open Access Journals (Sweden)

    Bin Zhou

    2014-10-01

    Full Text Available Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV. Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1. This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2 showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

  1. Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

    Science.gov (United States)

    Zhou, Bin; Ma, Jingjiao; Liu, Qinfang; Bawa, Bhupinder; Wang, Wei; Shabman, Reed S; Duff, Michael; Lee, Jinhwa; Lang, Yuekun; Cao, Nan; Nagy, Abdou; Lin, Xudong; Stockwell, Timothy B; Richt, Juergen A; Wentworth, David E; Ma, Wenjun

    2014-10-01

    Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

  2. Proteomic analysis of mitochondria in respiratory epithelial cells infected with human respiratory syncytial virus and functional implications for virus and cell biology.

    Science.gov (United States)

    Munday, Diane C; Howell, Gareth; Barr, John N; Hiscox, Julian A

    2015-03-01

    The aim of this study was to quantitatively characterise the mitochondrial proteome of airway epithelial cells infected with human respiratory syncytial virus (HRSV), a major cause of paediatric illness. Quantitative proteomics, underpinned by stable isotope labelling with amino acids in cell culture, coupled to LC-MS/MS, was applied to mitochondrial fractions prepared from HRSV-infected and mock-infected cells 12 and 24 h post-infection. Datasets were analysed using ingenuity pathway analysis, and the results were validated and characterised using bioimaging, targeted inhibition and gene depletion. The data quantitatively indicated that antiviral signalling proteins converged on mitochondria during HRSV infection. The mitochondrial receptor protein Tom70 was found to act in an antiviral manner, while its chaperone, Hsp90, was confirmed to be a positive viral factor. Proteins associated with different organelles were also co-enriched in the mitochondrial fractions from HRSV-infected cells, suggesting that alterations in organelle dynamics and membrane associations occur during virus infection. Protein and pathway-specific alterations occur to the mitochondrial proteome in a spatial and temporal manner during HRSV infection, suggesting that this organelle may have altered functions. These could be targeted as part of potential therapeutic strategies to disrupt virus biology. © 2014 Royal Pharmaceutical Society.

  3. Promotion of Hendra Virus Replication by MicroRNA 146a

    Science.gov (United States)

    Marsh, Glenn A.; Jenkins, Kristie A.; Gantier, Michael P.; Tizard, Mark L.; Middleton, Deborah; Lowenthal, John W.; Haining, Jessica; Izzard, Leonard; Gough, Tamara J.; Deffrasnes, Celine; Stambas, John; Robinson, Rachel; Heine, Hans G.; Pallister, Jackie A.; Foord, Adam J.; Bean, Andrew G.; Wang, Lin-Fa

    2013-01-01

    Hendra virus is a highly pathogenic zoonotic paramyxovirus in the genus Henipavirus. Thirty-nine outbreaks of Hendra virus have been reported since its initial identification in Queensland, Australia, resulting in seven human infections and four fatalities. Little is known about cellular host factors impacting Hendra virus replication. In this work, we demonstrate that Hendra virus makes use of a microRNA (miRNA) designated miR-146a, an NF-κB-responsive miRNA upregulated by several innate immune ligands, to favor its replication. miR-146a is elevated in the blood of ferrets and horses infected with Hendra virus and is upregulated by Hendra virus in human cells in vitro. Blocking miR-146a reduces Hendra virus replication in vitro, suggesting a role for this miRNA in Hendra virus replication. In silico analysis of miR-146a targets identified ring finger protein (RNF)11, a member of the A20 ubiquitin editing complex that negatively regulates NF-κB activity, as a novel component of Hendra virus replication. RNA interference-mediated silencing of RNF11 promotes Hendra virus replication in vitro, suggesting that increased NF-κB activity aids Hendra virus replication. Furthermore, overexpression of the IκB superrepressor inhibits Hendra virus replication. These studies are the first to demonstrate a host miRNA response to Hendra virus infection and suggest an important role for host miRNAs in Hendra virus disease. PMID:23345523

  4. Respiratory Syncytial Virus Infections in Infants: Detel1ninants of Clinical Severity

    NARCIS (Netherlands)

    A.H. Brandenburg (Afke)

    2000-01-01

    textabstractIn 1955 a virus was isolated by Morris et al. from a chimpanzee with an upper respiratory tract infection. This apparently new virus was originally called chimpanzee coryza agent. Soon aftclwards, when it was isolated from children with respiratory disease, it became clear that this

  5. Whole genome sequencing and evolutionary analysis of human respiratory syncytial virus A and B from Milwaukee, WI 1998-2010.

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    Cecilia Rebuffo-Scheer

    Full Text Available BACKGROUND: Respiratory Syncytial Virus (RSV is the leading cause of lower respiratory-tract infections in infants and young children worldwide. Despite this, only six complete genome sequences of original strains have been previously published, the most recent of which dates back 35 and 26 years for RSV group A and group B respectively. METHODOLOGY/PRINCIPAL FINDINGS: We present a semi-automated sequencing method allowing for the sequencing of four RSV whole genomes simultaneously. We were able to sequence the complete coding sequences of 13 RSV A and 4 RSV B strains from Milwaukee collected from 1998-2010. Another 12 RSV A and 5 RSV B strains sequenced in this study cover the majority of the genome. All RSV A and RSV B sequences were analyzed by neighbor-joining, maximum parsimony and Bayesian phylogeny methods. Genetic diversity was high among RSV A viruses in Milwaukee including the circulation of multiple genotypes (GA1, GA2, GA5, GA7 with GA2 persisting throughout the 13 years of the study. However, RSV B genomes showed little variation with all belonging to the BA genotype. For RSV A, the same evolutionary patterns and clades were seen consistently across the whole genome including all intergenic, coding, and non-coding regions sequences. CONCLUSIONS/SIGNIFICANCE: The sequencing strategy presented in this work allows for RSV A and B genomes to be sequenced simultaneously in two working days and with a low cost. We have significantly increased the amount of genomic data that is available for both RSV A and B, providing the basic molecular characteristics of RSV strains circulating in Milwaukee over the last 13 years. This information can be used for comparative analysis with strains circulating in other communities around the world which should also help with the development of new strategies for control of RSV, specifically vaccine development and improvement of RSV diagnostics.

  6. Morphogenesis of respiratory syncytial virus in human primary nasal ciliated epithelial cells occurs at surface membrane microdomains that are distinct from cilia

    International Nuclear Information System (INIS)

    Jumat, Muhammad Raihan; Yan, Yan; Ravi, Laxmi Iyer; Wong, Puisan; Huong, Tra Nguyen; Li, Chunwei; Tan, Boon Huan; Wang, De Yun; Sugrue, Richard J.

    2015-01-01

    The distribution of cilia and the respiratory syncytial virus (RSV) nucleocapsid (N) protein, fusion (F) protein, attachment (G) protein, and M2-1 protein in human ciliated nasal epithelial cells was examined at between 1 and 5 days post-infection (dpi). All virus structural proteins were localized at cell surface projections that were distinct from cilia. The F protein was also trafficked into the cilia, and while its presence increased as the infection proceeded, the N protein was not detected in the cilia at any time of infection. The presence of the F protein in the cilia correlated with cellular changes in the cilia and reduced cilia function. At 5 dpi extensive cilia loss and further reduced cilia function was noted. These data suggested that although RSV morphogenesis occurs at non-cilia locations on ciliated nasal epithelial cells, RSV infection induces changes in the cilia body that leads to extensive cilia loss. - Highlights: • Respiratory syncytial virus (RSV) infects nasal ciliated epithelial cells. • Virus morphogenesis occurs within filamentous projections distinct from cilia. • The RSV N protein was not detected in the cilia at any time during infection. • Trafficking of the F protein into the cilia occurred early in infection. • Presence of the F protein in cilia correlated with impaired cilia function

  7. Morphogenesis of respiratory syncytial virus in human primary nasal ciliated epithelial cells occurs at surface membrane microdomains that are distinct from cilia

    Energy Technology Data Exchange (ETDEWEB)

    Jumat, Muhammad Raihan [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Yan, Yan [Department of Otolaryngology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228 (Singapore); Ravi, Laxmi Iyer [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Wong, Puisan [Detection and Diagnostics Laboratory, DSO National Laboratories, 27 Medical Drive, Singapore 117510 (Singapore); Huong, Tra Nguyen [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore); Li, Chunwei [Department of Otolaryngology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228 (Singapore); Tan, Boon Huan [Detection and Diagnostics Laboratory, DSO National Laboratories, 27 Medical Drive, Singapore 117510 (Singapore); Wang, De Yun [Department of Otolaryngology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228 (Singapore); Sugrue, Richard J., E-mail: rjsugrue@ntu.edu.sg [School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551 (Singapore)

    2015-10-15

    The distribution of cilia and the respiratory syncytial virus (RSV) nucleocapsid (N) protein, fusion (F) protein, attachment (G) protein, and M2-1 protein in human ciliated nasal epithelial cells was examined at between 1 and 5 days post-infection (dpi). All virus structural proteins were localized at cell surface projections that were distinct from cilia. The F protein was also trafficked into the cilia, and while its presence increased as the infection proceeded, the N protein was not detected in the cilia at any time of infection. The presence of the F protein in the cilia correlated with cellular changes in the cilia and reduced cilia function. At 5 dpi extensive cilia loss and further reduced cilia function was noted. These data suggested that although RSV morphogenesis occurs at non-cilia locations on ciliated nasal epithelial cells, RSV infection induces changes in the cilia body that leads to extensive cilia loss. - Highlights: • Respiratory syncytial virus (RSV) infects nasal ciliated epithelial cells. • Virus morphogenesis occurs within filamentous projections distinct from cilia. • The RSV N protein was not detected in the cilia at any time during infection. • Trafficking of the F protein into the cilia occurred early in infection. • Presence of the F protein in cilia correlated with impaired cilia function.

  8. The relationship between antibody status to bovine corona virus and bovine respiratory syncytial virus and disease incidence, reproduction and herd characteristics in dairy herds

    Directory of Open Access Journals (Sweden)

    Tråvén Madeleine

    2010-06-01

    Full Text Available Abstract Background Bovine respiratory syncytial virus (BRSV and bovine corona virus (BCV affects cattle worldwide. Our objective was to evaluate the effects of these infections on general health and reproduction parameters measurable on herd level and to explore the association between antibody status and some herd characteristics. Methods We collected a pooled milk sample from five primiparous cows from 79 Swedish dairy herds in September 2006. The samples were analysed for immunoglobulin G antibodies to BCV and BRSV with indirect enzyme-linked immunosorbent assays. Herd level data from 1 September 2005 to 30 August 2006 were accessed retrospectively. The location of the herds was mapped using a geographical information system. Results Ten herds were antibody negative to both viruses and were compared with 69 herds positive to BCV or BRSV or both. Positive herds had a higher (P = 0.001 bulk tank milk somatic cell count (BMSCC compared with negative herds. The medians for all other analyzed health and reproductive parameters were consistently in favour of the herds negative to both viruses although the differences were not statistically significant. A higher proportion (P = 0.01 of herds used professional technicians for artificial insemination, rather than farm personnel, amongst the 33 herds negative to BCV compared with the 46 positive herds. Conclusions Our result shows that herds that were antibody positive to BCV and/or BRSV had a higher BMSCC compared with herds negative to BCV and BRSV. There was also tendency that negative herds had a better general herd health compared with positive. A higher proportion amongst the BCV negative herds used external technicians for AI instead of farm personnel, indicating that it is possible to avoid infection although having regular visits. Negative herds were located in close proximity to positive herds, indicating that local spread and airborne transmission between herds might not be of great

  9. Respiratory syncytial virus infections enhance cigarette smoke induced COPD in mice.

    Directory of Open Access Journals (Sweden)

    Robert F Foronjy

    Full Text Available Respiratory syncytial viral (RSV infections are a frequent cause of chronic obstructive pulmonary disease (COPD exacerbations, which are a major factor in disease progression and mortality. RSV is able to evade antiviral defenses to persist in the lungs of COPD patients. Though RSV infection has been identified in COPD, its contribution to cigarette smoke-induced airway inflammation and lung tissue destruction has not been established. Here we examine the long-term effects of cigarette smoke exposure, in combination with monthly RSV infections, on pulmonary inflammation, protease production and remodeling in mice. RSV exposures enhanced the influx of macrophages, neutrophils and lymphocytes to the airways of cigarette smoke exposed C57BL/6J mice. This infiltration of cells was most pronounced around the vasculature and bronchial airways. By itself, RSV caused significant airspace enlargement and fibrosis in mice and these effects were accentuated with concomitant smoke exposure. Combined stimulation with both smoke and RSV synergistically induced cytokine (IL-1α, IL-17, IFN-γ, KC, IL-13, CXCL9, RANTES, MIF and GM-CSF and protease (MMP-2, -8, -12, -13, -16 and cathepsins E, S, W and Z expression. In addition, RSV exposure caused marked apoptosis within the airways of infected mice, which was augmented by cigarette smoke exposure. RSV and smoke exposure also reduced protein phosphatase 2A (PP2A and protein tyrosine phosphates (PTP1B expression and activity. This is significant as these phosphatases counter smoke-induced inflammation and protease expression. Together, these findings show for the first time that recurrent RSV infection markedly enhances inflammation, apoptosis and tissue destruction in smoke-exposed mice. Indeed, these results indicate that preventing RSV transmission and infection has the potential to significantly impact on COPD severity and progression.

  10. Evidence that maturation of the N-linked glycans of the respiratory syncytial virus (RSV) glycoproteins is required for virus-mediated cell fusion: The effect of α-mannosidase inhibitors on RSV infectivity

    International Nuclear Information System (INIS)

    McDonald, Terence P.; Jeffree, Chris E.; Li, Ping; Rixon, Helen W. McL.; Brown, Gaie; Aitken, James D.; MacLellan, Kirsty; Sugrue, Richard J.

    2006-01-01

    Glycan heterogeneity of the respiratory syncytial virus (RSV) fusion (F) protein was demonstrated by proteomics. The effect of maturation of the virus glycoproteins-associated glycans on virus infectivity was therefore examined using the α-mannosidase inhibitors deoxymannojirimycin (DMJ) and swainsonine (SW). In the presence of SW the N-linked glycans on the F protein appeared in a partially mature form, whereas in the presence of DMJ no maturation of the glycans was observed. Neither inhibitor had a significant effect on G protein processing or on the formation of progeny virus. Although the level of infectious virus and syncytia formation was not significantly affected by SW-treatment, DMJ-treatment correlated with a one hundred-fold reduction in virus infectivity. Our data suggest that glycan maturation of the RSV glycoproteins, in particular those on the F protein, is an important step in virus maturation and is required for virus infectivity

  11. Trigocherrierin A, a Potent Inhibitor of Chikungunya Virus Replication

    Directory of Open Access Journals (Sweden)

    Mélanie Bourjot

    2014-03-01

    Full Text Available Trigocherrierin A (1 and trigocherriolide E (2, two new daphnane diterpenoid orthoesters (DDOs, and six chlorinated analogues, trigocherrins A, B, F and trigocherriolides A–C, were isolated from the leaves of Trigonostemon cherrieri. Their structures were identified by mass spectrometry, extensive one- and two-dimensional NMR spectroscopy and through comparison with data reported in the literature. These compounds are potent and selective inhibitors of chikungunya virus (CHIKV replication. Among the DDOs isolated, compound 1 exhibited the strongest anti-CHIKV activity (EC50 = 0.6 ± 0.1 µM, SI = 71.7.

  12. Fowl plague virus replication in mammalian cell-avian erythrocyte heterokaryons: studies concerning the actinomycin D and ultra-violet lig sensitive phase in influenza virus replication

    International Nuclear Information System (INIS)

    Kelly, D.C.; Dimmock, N.J.

    1974-01-01

    The replication of fowl plague virus in BHK and L cells specifically blocked prior to infection with inhibitors of influenza virus replication (actinomycin D and ultraviolet light irradiation) has been studied by the introduction of a metabolically dormant avian erythrocyte nucleus. This permits the synthesis of just the influenza virus nucleoprotein in actinomycin D (but not ultraviolet light) blocked cells. The NP antigen is first detected in the avian erythrocyte nucleus and subsequently in the heterokaryon cytoplasm

  13. Phosphorylation of NS5A Serine-235 is essential to hepatitis C virus RNA replication and normal replication compartment formation

    Energy Technology Data Exchange (ETDEWEB)

    Eyre, Nicholas S., E-mail: nicholas.eyre@adelaide.edu.au [School of Biological Sciences and Research Centre for Infectious Diseases, University of Adelaide, Adelaide (Australia); Centre for Cancer Biology, SA Pathology, Adelaide (Australia); Hampton-Smith, Rachel J.; Aloia, Amanda L. [School of Biological Sciences and Research Centre for Infectious Diseases, University of Adelaide, Adelaide (Australia); Centre for Cancer Biology, SA Pathology, Adelaide (Australia); Eddes, James S. [Adelaide Proteomics Centre, School of Biological Sciences, University of Adelaide, Adelaide (Australia); Simpson, Kaylene J. [Victorian Centre for Functional Genomics, Peter MacCallum Cancer Centre, East Melbourne (Australia); The Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville (Australia); Hoffmann, Peter [Adelaide Proteomics Centre, School of Biological Sciences, University of Adelaide, Adelaide (Australia); Institute for Photonics and Advanced Sensing (IPAS), University of Adelaide, Adelaide (Australia); Beard, Michael R. [School of Biological Sciences and Research Centre for Infectious Diseases, University of Adelaide, Adelaide (Australia); Centre for Cancer Biology, SA Pathology, Adelaide (Australia)

    2016-04-15

    Hepatitis C virus (HCV) NS5A protein is essential for HCV RNA replication and virus assembly. Here we report the identification of NS5A phosphorylation sites Ser-222, Ser-235 and Thr-348 during an infectious HCV replication cycle and demonstrate that Ser-235 phosphorylation is essential for HCV RNA replication. Confocal microscopy revealed that both phosphoablatant (S235A) and phosphomimetic (S235D) mutants redistribute NS5A to large juxta-nuclear foci that display altered colocalization with known replication complex components. Using electron microscopy (EM) we found that S235D alters virus-induced membrane rearrangements while EM using ‘APEX2’-tagged viruses demonstrated S235D-mediated enrichment of NS5A in irregular membranous foci. Finally, using a customized siRNA screen of candidate NS5A kinases and subsequent analysis using a phospho-specific antibody, we show that phosphatidylinositol-4 kinase III alpha (PI4KIIIα) is important for Ser-235 phosphorylation. We conclude that Ser-235 phosphorylation of NS5A is essential for HCV RNA replication and normal replication complex formation and is regulated by PI4KIIIα. - Highlights: • NS5A residues Ser-222, Ser-235 and Thr-348 are phosphorylated during HCV infection. • Phosphorylation of Ser-235 is essential to HCV RNA replication. • Mutation of Ser-235 alters replication compartment localization and morphology. • Phosphatidylinositol-4 kinase III alpha is important for Ser-235 phosphorylation.

  14. Evaluation of a multiplex immunoassay for bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk against two indirect ELISAs using latent class analysis

    DEFF Research Database (Denmark)

    Toftaker, Ingrid; Toft, Nils; Stokstad, Maria

    2018-01-01

    Bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCV) are responsible for respiratory disease and diarrhea in cattle worldwide. The Norwegian control program against these infections is based on herd-level diagnosis using a new multiplex immunoassay. The objective of this study...... was to estimate sensitivity and specificity across different cut-off values for the MVD-Enferplex BCV/BRSV multiplex, by comparing them to a commercially available ELISA, the SVANOVIR® BCV-Ab and SVANOVIR® BRSV-Ab, respectively. We analyzed bulk tank milk samples from 360 herds in a low- and 360 herds in a high...

  15. Severe respiratory syncytial virus bronchiolitis in infants is associated with reduced airway interferon gamma and substance P.

    Directory of Open Access Journals (Sweden)

    Malcolm G Semple

    2007-10-01

    Full Text Available Severe human respiratory syncytial virus (hRSV bronchiolitis in previously well infants may be due to differences in the innate immune response to hRSV infection.to determine if factors mediating proposed mechanisms for severe bronchiolitis differ with severity of disease.197 infants admitted to hospital with hRSV bronchiolitis were recruited and grouped according to no oxygen requirement (n = 27, oxygen dependence (n = 114 or mechanical ventilation (n = 56. We collected clinical data, nasopharyngeal aspirate (NPA and if ventilated bronchoalveolar lavage (BAL. Interferon-gamma (IFN-gamma, substance P (SP, interleukin 9 (IL-9, urea and hRSV load, were measured in cell free supernatant from NPA and BAL. Multivariate analysis compared independent effects of clinical, virological and immunological variables upon disease severity. IFN-gamma and SP concentrations were lower in NPA from infants who required oxygen or mechanical ventilation. Viral load and IL-9 concentrations were high but did not vary with severity of disease. Independent predictors of severe disease (in diminishing size of effect were low weight on admission, low gestation at birth, low NPA IFN-gamma and NPA SP. Nasal airway sampling appears to be a useful surrogate for distal airway sampling since concentrations of IFN-gamma, SP, IL-9 and viral load in NPA correlate with the same in BAL.Our data support two proposed mechanisms for severe hRSV disease; reduced local IFN-gamma response and SP mediated inflammation. We found large amounts of hRSV and IL-9 in airways secretions from the upper and lower respiratory tract but could not associate these with disease severity.

  16. Epidemiology and Molecular Characterization of Human Respiratory Syncytial Virus in Senegal after Four Consecutive Years of Surveillance, 2012–2015

    Science.gov (United States)

    Cisse, El Hadj Abdel Kader; Kiori, Davy E.; Sarr, Fatoumata Diene; Sy, Sara; Goudiaby, Debora; Richard, Vincent; Niang, Mbayame Ndiaye

    2016-01-01

    Background The burden of respiratory syncytial virus (RSV) infection remains poorly defined in Africa. To address this, we carried out a descriptive and retrospective pilot study, with a focus on the epidemiology of RSV in Senegal after 4 years of surveillance. Methodology and Results From January 2012 to October 2015 swabs were collected from consenting ILI outpatients. Viral detection was performed using RV16 kit enabling direct subtyping of RSV-A and B. For the molecular characterization of HRSV, the second hypervariable region of the Glycoprotein (G) gene was targeted for sequencing. We enrolled 5338 patients with 2803 children younger than five years of age (52.5%). 610 (11.4%) were positive for RSV infection: 276 (45.2%) were group A infections, 334 (54.8%) were group B infections and 21 (3.4%) were A/B co-infections. RSV detection rate is significantly higher (P Senegal clustered with strains that were previously assigned NA1 and novel ON1 genotype sequences. RSV-B sequences from Senegal clustered with the BA9 genotype. At the amino acid level, RSV-A strains from Senegal show proximity with the genotype ON1 characterized by a 72 nt insertion in G, resulting in 24 extra amino acids of which 23 are duplications of aa 261–283. Conclusion Globally our results show a clear circulation pattern of RSV in the second half of each year, between June and September and possibly extending into November, with children under 5 being more susceptible. Molecular studies identified the novel strains ON1 and BA9 as the major genotypes circulating in Senegal between 2012 and 2015. PMID:27315120

  17. Epidemiology and Molecular Characterization of Human Respiratory Syncytial Virus in Senegal after Four Consecutive Years of Surveillance, 2012-2015.

    Science.gov (United States)

    Fall, Amary; Dia, Ndongo; Cisse, El Hadj Abdel Kader; Kiori, Davy E; Sarr, Fatoumata Diene; Sy, Sara; Goudiaby, Debora; Richard, Vincent; Niang, Mbayame Ndiaye

    2016-01-01

    The burden of respiratory syncytial virus (RSV) infection remains poorly defined in Africa. To address this, we carried out a descriptive and retrospective pilot study, with a focus on the epidemiology of RSV in Senegal after 4 years of surveillance. From January 2012 to October 2015 swabs were collected from consenting ILI outpatients. Viral detection was performed using RV16 kit enabling direct subtyping of RSV-A and B. For the molecular characterization of HRSV, the second hypervariable region of the Glycoprotein (G) gene was targeted for sequencing. We enrolled 5338 patients with 2803 children younger than five years of age (52.5%). 610 (11.4%) were positive for RSV infection: 276 (45.2%) were group A infections, 334 (54.8%) were group B infections and 21 (3.4%) were A/B co-infections. RSV detection rate is significantly higher (P Senegal clustered with strains that were previously assigned NA1 and novel ON1 genotype sequences. RSV-B sequences from Senegal clustered with the BA9 genotype. At the amino acid level, RSV-A strains from Senegal show proximity with the genotype ON1 characterized by a 72 nt insertion in G, resulting in 24 extra amino acids of which 23 are duplications of aa 261-283. Globally our results show a clear circulation pattern of RSV in the second half of each year, between June and September and possibly extending into November, with children under 5 being more susceptible. Molecular studies identified the novel strains ON1 and BA9 as the major genotypes circulating in Senegal between 2012 and 2015.

  18. Prospective validation of a prognostic model for respiratory syncytial virus bronchiolitis in late preterm infants: a multicenter birth cohort study.

    Directory of Open Access Journals (Sweden)

    Maarten O Blanken

    Full Text Available This study aimed to update and validate a prediction rule for respiratory syncytial virus (RSV hospitalization in preterm infants 33-35 weeks gestational age (WGA.The RISK study consisted of 2 multicenter prospective birth cohorts in 41 hospitals. Risk factors were assessed at birth among healthy preterm infants 33-35 WGA. All hospitalizations for respiratory tract infection were screened for proven RSV infection by immunofluorescence or polymerase chain reaction. Multivariate logistic regression analysis was used to update an existing prediction model in the derivation cohort (n = 1,227. In the validation cohort (n = 1,194, predicted versus actual RSV hospitalization rates were compared to determine validity of the model.RSV hospitalization risk in both cohorts was comparable (5.7% versus 4.9%. In the derivation cohort, a prediction rule to determine probability of RSV hospitalization was developed using 4 predictors: family atopy (OR 1.9; 95%CI, 1.1-3.2, birth period (OR 2.6; 1.6-4.2, breastfeeding (OR 1.7; 1.0-2.7 and siblings or daycare attendance (OR 4.7; 1.7-13.1. The model showed good discrimination (c-statistic 0.703; 0.64-0.76, 0.702 after bootstrapping. External validation showed good discrimination and calibration (c-statistic 0.678; 0.61-0.74.Our prospectively validated prediction rule identifies infants at increased RSV hospitalization risk, who may benefit from targeted preventive interventions. This prediction rule can facilitate country-specific, cost-effective use of RSV prophylaxis in late preterm infants.

  19. Age related changes in T cell mediated immune response and effector memory to Respiratory Syncytial Virus (RSV in healthy subjects

    Directory of Open Access Journals (Sweden)

    Campoccia Giuseppe

    2010-10-01

    Full Text Available Abstract Respiratory syncytial virus (RSV is the major pathogen causing respiratory disease in young infants and it is an important cause of serious illness in the elderly since the infection provides limited immune protection against reinfection. In order to explain this phenomenon, we investigated whether healthy adults of different age (20-40; 41-60 and > 60 years, have differences in central and effector memory, RSV-specific CD8+ T cell memory immune response and regulatory T cell expression status. In the peripheral blood of these donors, we were unable to detect any age related difference in term of central (CD45RA-CCR7+ and effector (CD45RA-CCR7- memory T cell frequency. On the contrary, we found a significant increase in immunosuppressive regulatory (CD4+25+FoxP3+ T cells (Treg in the elderly. An immunocytofluorimetric RSV pentamer analysis performed on these donors' peripheral blood mononuclear cells (PBMCs, in vitro sensitized against RSV antigen, revealed a marked decline in long-lasting RSV specific CD8+ memory T cell precursors expressing interleukin 7 receptor α (IL-7Rα, in the elderly. This effect was paralleled by a progressive switch from a Th1 (IFN-γ and TNF-α to a Th2 (IL-10 functional phenotype. On the contrary, an increase in Treg was observed with aging. The finding of Treg over-expression status, a prominent Th2 response and an inefficient RSV-specific effector memory CD8+ T cell expansion in older donors could explain the poor protection against RSV reinfection and the increased risk to develop an RSV-related severe illness in this population. Our finding also lays the basis for new therapeutic perspectives that could limit or prevent severe RSV infection in elderly.

  20. Respiratory syncytial virus: a systematic scientometric analysis of the global publication output and the gender distribution of publishing authors.

    Science.gov (United States)

    Brüggmann, Dörthe; Köster, Corinna; Klingelhöfer, Doris; Bauer, Jan; Ohlendorf, Daniela; Bundschuh, Matthias; Groneberg, David A

    2017-07-26

    Worldwide, the respiratory syncytial virus (RSV) represents the predominant viral agent causing bronchiolitis and pneumonia in children. To conduct research and tackle existing healthcare disparities, RSV-related research activities around the globe need to be described. Hence, we assessed the associated scientific output (represented by research articles) by geographical, chronological and socioeconomic criteria and analysed the authors publishing in the field by gender. Also, the 15 most cited articles and the most prolific journals were identified for RSV research. Retrospective, descriptive study. The NewQIS (New Quality and Quantity Indices in Science) platform was employed to identify RSV-related articles published in the Web of Science until 2013. We performed a numerical analysis of all articles, and examined citation-based aspects (eg, citation rates); results were visualised by density equalising mapping tools. We identified 4600 RSV-related articles. The USA led the field; US-American authors published 2139 articles (46.5%% of all identified articles), which have been cited 83 000 times. When output was related to socioeconomic benchmarks such as gross domestic product or Research and Development expenditures, Guinea-Bissau, The Gambia and Chile were ranked in leading positions. A total of 614 articles on RSV (13.34% of all articles) were attributed to scientific collaborations. These were primarily established between high-income countries. The gender analysis indicated that male scientists dominated in all countries except Brazil. The majority of RSV-related research articles originated from high-income countries whereas developing nations showed only minimal publication productivity and were barely part of any collaborative networks. Hence, research capacity in these nations should be increased in order to assist in addressing inequities in resource allocation and the clinical burden of RSV in these countries. © Article author(s) (or their employer

  1. Effects of formalin-inactivated respiratory syncytial virus (FI-RSV in the perinatal lamb model of RSV.

    Directory of Open Access Journals (Sweden)

    Rachel J Derscheid

    Full Text Available Respiratory syncytial virus (RSV is the most frequent cause of bronchiolitis in infants and children worldwide. There are currently no licensed vaccines or effective antivirals. The lack of a vaccine is partly due to increased caution following the aftermath of a failed clinical trial of a formalin-inactivated RSV vaccine (FI-RSV conducted in the 1960's that led to enhanced disease, necessitating hospitalization of 80% of vaccine recipients and resulting in two fatalities. Perinatal lamb lungs are similar in size, structure and physiology to those of human infants and are susceptible to human strains of RSV that induce similar lesions as those observed in infected human infants. We sought to determine if perinatal lambs immunized with FI-RSV would develop key features of vaccine-enhanced disease. This was tested in colostrum-deprived lambs immunized at 3-5 days of age with FI-RSV followed two weeks later by RSV infection. The FI-RSV-vaccinated lambs exhibited several key features of RSV vaccine-enhanced disease, including reduced RSV titers in bronchoalveolar lavage fluid and lung, and increased infiltration of peribronchiolar and perivascular lymphocytes compared to lambs either undergoing an acute RSV infection or naïve controls; all features of RSV vaccine-enhanced disease. These results represent a first step proof-of-principle demonstration that the lamb can develop altered responses to RSV following FI-RSV vaccination. The lamb model may be useful for future mechanistic studies as well as the assessment of RSV vaccines designed for infants.

  2. Vaccine Induced Herd Immunity for Control of Respiratory Syncytial Virus Disease in a Low-Income Country Setting.

    Directory of Open Access Journals (Sweden)

    Timothy M Kinyanjui

    Full Text Available Respiratory syncytial virus (RSV is globally ubiquitous, and infection during the first six months of life is a major risk for severe disease and hospital admission; consequently RSV is the most important viral cause of respiratory morbidity and mortality in young children. Development of vaccines for young infants is complicated by the presence of maternal antibodies and immunological immaturity, but vaccines targeted at older children avoid these problems. Vaccine development for young infants has been unsuccessful, but this is not the case for older children (> 6 m. Would vaccinating older children have a significant public health impact? We developed a mathematical model to explore the benefits of a vaccine against RSV.We have used a deterministic age structured model capturing the key epidemiological characteristics of RSV and performed a statistical maximum-likelihood fit to age-specific hospitalization data from a developing country setting. To explore the effects of vaccination under different mixing assumptions, we included two versions of contact matrices: one from a social contact diary study, and the second a synthesised construction based on demographic data. Vaccination is assumed to elicit an immune response equivalent to primary infection. Our results show that immunisation of young children (5-10 m is likely to be a highly effective method of protection of infants (<6 m against hospitalisation. The majority benefit is derived from indirect protection (herd immunity. A full sensitivity and uncertainty analysis using Latin Hypercube Sampling of the parameter space shows that our results are robust to model structure and model parameters.This result suggests that vaccinating older infants and children against RSV can have a major public health benefit.

  3. Replication of avian influenza viruses in equine tracheal epithelium but not in horses

    OpenAIRE

    Chambers, Thomas M.; Balasuriya, Udeni B. R.; Reedy, Stephanie E.; Tiwari, Ashish

    2013-01-01

    We evaluated a hypothesis that horses are susceptible to avian influenza viruses by in vitro testing, using explanted equine tracheal epithelial cultures, and in vivo testing by aerosol inoculation of ponies. Results showed that several subtypes of avian influenza viruses detectably replicated in vitro. Three viruses with high in vitro replication competence were administered to ponies. None of the three demonstrably replicated or caused disease signs in ponies. While these results do not exh...

  4. Interferon lambda inhibits dengue virus replication in epithelial cells.

    Science.gov (United States)

    Palma-Ocampo, Helen K; Flores-Alonso, Juan C; Vallejo-Ruiz, Verónica; Reyes-Leyva, Julio; Flores-Mendoza, Lilian; Herrera-Camacho, Irma; Rosas-Murrieta, Nora H; Santos-López, Gerardo

    2015-09-28

    In viral disease, infection is controlled at the cellular level by type I interferon (IFN-I), but dengue virus (DENV) has the ability to inhibit this response. Type III interferon, also known as lambda IFN (IFN-III or IFN-λ), is a complementary pathway to the antiviral response by IFN-I. This work analyzed the IFN-λ (IFN-III) mediated antiviral response against DENV serotype 2 (DENV-2) infection. Dengue fever patients were sampled to determine their IFN-λ levels by ELISA. To study the IFN-λ response during DENV infection we selected the epithelial cell line C33-A, and we demonstrated that it is permissive to DENV-2 infection. The effect of IFN-λ on virus replication was determined in these cells, in parallel to the expression of IFN-stimulated genes (ISGs), and Suppressor of Cytokine Signaling (SOCS), genes measured by RT-qPCR. We found increased (~1.8 times) serological IFN-λ in dengue fever patients compared to healthy blood donors. IFN-λ inhibited DENV-2 replication in a dose-dependent manner in vitro. The reduction of viral titer corresponded with increased ISG mRNA levels (MX1 and OAS1), with the highest inhibition occurring at ISG's peak expression. Presence of IFN-negative regulators, SOCS1 and SOCS3, during DENV-2 infection was associated with reduced IFN-λ1 expression. Evidence described here suggests that IFN-λ is a good candidate inhibitor of viral replication in dengue infection. Mechanisms for the cellular and organismal interplay between DENV and IFN- λ need to be further studied as they could provide insights into strategies to treat this disease. Furthermore, we report a novel epithelial model to study dengue infection in vitro.

  5. Respiratory syncytial virus (RSV bronchiolitis: comparative study of RSV groups A and B infected children

    Directory of Open Access Journals (Sweden)

    Selir M. Straliotto

    1994-03-01

    Full Text Available The grouping characteristics of 29 respiratory syncitial virus (RSV present in nasopharyngeal cells collectedfrom hospitalized children with bronchiolitis during the 1990RSVseason in Porto Alegre, RS, were analysed. Twenty-two were grouped as belonging to group A and 7 to group B. Cyanosis, oxigen therapy, cough, lenght of hospitalization and atelectasis were observed to be more frequently found within group B infected children. Other clinical signs and symptoms were similarly found in both groups.

  6. Hepatitis C virus translation preferentially depends on active RNA replication.

    Directory of Open Access Journals (Sweden)

    Helene Minyi Liu

    Full Text Available Hepatitis C virus (HCV RNA initiates its replication on a detergent-resistant membrane structure derived from the endoplasmic reticulum (ER in the HCV replicon cells. By performing a pulse-chase study of BrU-labeled HCV RNA, we found that the newly-synthesized HCV RNA traveled along the anterograde-membrane traffic and moved away from the ER. Presumably, the RNA moved to the site of translation or virion assembly in the later steps of viral life cycle. In this study, we further addressed how HCV RNA translation was regulated by HCV RNA trafficking. When the movement of HCV RNA from the site of RNA synthesis to the Golgi complex was blocked by nocodazole, an inhibitor of ER-Golgi transport, HCV protein translation was surprisingly enhanced, suggesting that the translation of viral proteins occurred near the site of RNA synthesis. We also found that the translation of HCV proteins was dependent on active RNA synthesis: inhibition of viral RNA synthesis by an NS5B inhibitor resulted in decreased HCV viral protein synthesis even when the total amount of intracellular HCV RNA remained unchanged. Furthermore, the translation activity of the replication-defective HCV replicons or viral RNA with an NS5B mutation was greatly reduced as compared to that of the corresponding wildtype RNA. By performing live cell labeling of newly synthesized HCV RNA and proteins, we further showed that the newly synthesized HCV proteins colocalized with the newly synthesized viral RNA, suggesting that HCV RNA replication and protein translation take place at or near the same site. Our findings together indicate that the translation of HCV RNA is coupled to RNA replication and that the both processes may occur at the same subcellular membrane compartments, which we term the replicasome.

  7. Nasally administered Lactobacillus rhamnosus strains differentially modulate respiratory antiviral immune responses and induce protection against respiratory syncytial virus infection.

    Science.gov (United States)

    Tomosada, Yohsuke; Chiba, Eriko; Zelaya, Hortensia; Takahashi, Takuya; Tsukida, Kohichiro; Kitazawa, Haruki; Alvarez, Susana; Villena, Julio

    2013-08-15

    Some studies have shown that nasally administered immunobiotics had the potential to improve the outcome of influenza virus infection. However, the capacity of immunobiotics to improve protection against respiratory syncytial virus (RSV) infection was not investigated before. The aims of this study were: a) to evaluate whether the nasal administration of Lactobacillus rhamnosus CRL1505 (Lr05) and L. rhamnosus CRL1506 (Lr06) are able to improve respiratory antiviral defenses and beneficially modulate the immune response triggered by TLR3/RIG-I activation; b) to investigate whether viability of Lr05 or Lr06 is indispensable to modulate respiratory immunity and; c) to evaluate the capacity of Lr05 and Lr06 to improve the resistance of infant mice against RSV infection. Nasally administered Lr05 and Lr06 differentially modulated the TLR3/RIG-I-triggered antiviral respiratory immune response. Lr06 administration significantly modulated the production of IFN-α, IFN-β and IL-6 in the response to poly(I:C) challenge, while nasal priming with Lr05 was more effective to improve levels of IFN-γ and IL-10. Both viable Lr05 and Lr06 strains increased the resistance of infant mice to RSV infection while only heat-killed Lr05 showed a protective effect similar to those observed with viable strains. The present work demonstrated that nasal administration of immunobiotics is able to beneficially modulate the immune response triggered by TLR3/RIG-I activation in the respiratory tract and to increase the resistance of mice to the challenge with RSV. Comparative studies using two Lactobacillus rhamnosus strains of the same origin and with similar technological properties showed that each strain has an specific immunoregulatory effect in the respiratory tract and that they differentially modulate the immune response after poly(I:C) or RSV challenges, conferring different degree of protection and using distinct immune mechanisms. We also demonstrated in this work that it is possible

  8. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    International Nuclear Information System (INIS)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga; Luque, Daniel; Terrón, María C.; Calder, Lesley J.; Melero, José A.

    2014-01-01

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV F occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV F , we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV F at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy

  9. Polyclonal and monoclonal antibodies specific for the six-helix bundle of the human respiratory syncytial virus fusion glycoprotein as probes of the protein post-fusion conformation

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, Concepción; Mas, Vicente; Vázquez, Mónica; Cano, Olga [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Luque, Daniel; Terrón, María C. [Unidad de Microscopía Electrónica y Confocal, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain); Calder, Lesley J. [National Institute for Medical Research, MRC, Mill Hill, London NW7 1AA (United Kingdom); Melero, José A., E-mail: jmelero@isciii.es [Unidad de Biología Viral, Centro Nacional de Microbiología, Madrid (Spain); CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid (Spain)

    2014-07-15

    Human respiratory syncytial virus (hRSV) has two major surface glycoproteins (G and F) anchored in the lipid envelope. Membrane fusion promoted by hRSV{sub F} occurs via refolding from a pre-fusion form to a highly stable post-fusion state involving large conformational changes of the F trimer. One of these changes results in assembly of two heptad repeat sequences (HRA and HRB) into a six-helix bundle (6HB) motif. To assist in distinguishing pre- and post-fusion conformations of hRSV{sub F}, we have prepared polyclonal (α-6HB) and monoclonal (R145) rabbit antibodies specific for the 6HB. Among other applications, these antibodies were used to explore the requirements of 6HB formation by isolated protein segments or peptides and by truncated mutants of the F protein. Site-directed mutagenesis and electron microscopy located the R145 epitope in the post-fusion hRSV{sub F} at a site distantly located from previously mapped epitopes, extending the repertoire of antibodies that can decorate the F molecule. - Highlights: • Antibodies specific for post-fusion respiratory syncytial virus fusion protein are described. • Polyclonal antibodies were obtained in rabbit inoculated with chimeric heptad repeats. • Antibody binding required assembly of a six-helix bundle in the post-fusion protein. • A monoclonal antibody with similar structural requirements is also described. • Binding of this antibody to the post-fusion protein was visualized by electron microscopy.

  10. Viral replication. Structural basis for RNA replication by the hepatitis C virus polymerase.

    Science.gov (United States)

    Appleby, Todd C; Perry, Jason K; Murakami, Eisuke; Barauskas, Ona; Feng, Joy; Cho, Aesop; Fox, David; Wetmore, Diana R; McGrath, Mary E; Ray, Adrian S; Sofia, Michael J; Swaminathan, S; Edwards, Thomas E

    2015-02-13

    Nucleotide analog inhibitors have shown clinical success in the treatment of hepatitis C virus (HCV) infection, despite an incomplete mechanistic understanding of NS5B, the viral RNA-dependent RNA polymerase. Here we study the details of HCV RNA replication by determining crystal structures of stalled polymerase ternary complexes with enzymes, RNA templates, RNA primers, incoming nucleotides, and catalytic metal ions during both primed initiation and elongation of RNA synthesis. Our analysis revealed that highly conserved active-site residues in NS5B position the primer for in-line attack on the incoming nucleotide. A β loop and a C-terminal membrane-anchoring linker occlude the active-site cavity in the apo state, retract in the primed initiation assembly to enforce replication of the HCV genome from the 3' terminus, and vacate the active-site cavity during elongation. We investigated the incorporation of nucleotide analog inhibitors, including the clinically active metabolite formed by sofosbuvir, to elucidate key molecular interactions in the active site. Copyright © 2015, American Association for the Advancement of Science.

  11. Emetine inhibits replication of RNA and DNA viruses without generating drug-resistant virus variants.

    Science.gov (United States)

    Khandelwal, Nitin; Chander, Yogesh; Rawat, Krishan Dutt; Riyesh, Thachamvally; Nishanth, Chikkahonnaiah; Sharma, Shalini; Jindal, Naresh; Tripathi, Bhupendra N; Barua, Sanjay; Kumar, Naveen

    2017-08-01

    At a noncytotoxic concentration, emetine was found to inhibit replication of DNA viruses [buffalopoxvirus (BPXV) and bovine herpesvirus 1 (BHV-1)] as well as RNA viruses [peste des petits ruminants virus (PPRV) and Newcastle disease virus (NDV)]. Using the time-of-addition and virus step-specific assays, we showed that emetine treatment resulted in reduced synthesis of viral RNA (PPRV and NDV) and DNA (BPXV and BHV-1) as well as inhibiting viral entry (NDV and BHV-1). In addition, emetine treatment also resulted in decreased synthesis of viral proteins. In a cell free endogenous viral polymerase assay, emetine was found to significantly inhibit replication of NDV, but not BPXV genome, suggesting that besides directly inhibiting specific viral polymerases, emetine may also target other factors essentially required for efficient replication of the viral genome. Moreover, emetine was found to significantly inhibit BPXV-induced pock lesions on chorioallantoic membrane (CAM) along with associated mortality of embryonated chicken eggs. At a lethal dose 50 (LD 50 ) of 126.49 ng/egg and at an effective concentration 50 (EC 50 ) of 3.03 ng/egg, the therapeutic index of the emetine against BPXV was determined to be 41.74. Emetine was also found to significantly delay NDV-induced mortality in chicken embryos associated with reduced viral titers. Further, emetine-resistant mutants were not observed upon long-term (P = 25) sequential passage of BPXV and NDV in cell culture. Collectively, we have extended the effective antiviral activity of emetine against diverse groups of DNA and RNA viruses and propose that emetine could provide significant therapeutic value against some of these viruses without inducing an antiviral drug-resistant phenotype. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Comparison of Bovine coronavirus-specific and Bovine respiratory syncytial virus-specific antibodies in serum versus milk samples detected by enzyme-linked immunosorbent assay.

    Science.gov (United States)

    Ohlson, Anna; Blanco-Penedo, Isabel; Fall, Nils

    2014-01-01

    Bovine coronavirus (BCV; Betacoronavirus 1) and Bovine respiratory syncytial virus (BRSV) are significant causes of enteric and respiratory disease in beef and dairy cattle throughout the world. Indirect enzyme-linked immunosorbent assays are widely used to detect serum antibodies for herd monitoring and prevalence studies. In dairy herds, milk is more readily collected than serum. Hence, in order to investigate the test agreement between serum and milk, both serum and milk samples from 105 cows in 27 dairy herds were analyzed in parallel for presence of immunoglobulin G antibodies to BCV and BRSV. The Bland-Altman analyses of data demonstrated good agreement between serum and milk antibody titers for both viruses. The results indicate milk samples are sufficient for surveillance of antibodies to BCV and BRSV.

  13. Coxsackievirus B3 2A protease promotes encephalomyocarditis virus replication.

    Science.gov (United States)

    Song, Qin-Qin; Lu, Ming-Zhi; Song, Juan; Chi, Miao-Miao; Sheng, Lin-Jun; Yu, Jie; Luo, Xiao-Nuan; Zhang, Lu; Yao, Hai-Lan; Han, Jun

    2015-10-02

    To determine whether 2A protease of the enterovirus genus with type I internal ribosome entry site (IRES) effect on the viral replication of type II IRES, coxsackievirus B3(CVB3)-encoded protease 2A and encephalomyocarditis virus (EMCV) IRES (Type II)-dependent or cap-dependent report gene were transiently co-expressed in eukaryotic cells. We found that CVB3 2A protease not only inhibited translation of cap-dependent reporter genes through the cleavage of eIF4GI, but also conferred high EMCV IRES-dependent translation ability and promoted EMCV replication. Moreover, deletions of short motif (aa13-18 RVVNRH, aa65-70 KNKHYP, or aa88-93 PRRYQSH) resembling the nuclear localization signals (NLS) or COOH-terminal acidic amino acid motif (aa133-147 DIRDLLWLEDDAMEQ) of CVB3 2A protease decreased both its EMCV IRES-dependent translation efficiency and destroy its cleavage on eukaryotic initiation factor 4G (eIF4G) I. Our results may provide better understanding into more effective interventions and treatments for co-infection of viral diseases. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Burden of Respiratory Syncytial Virus Infection in South African Human Immunodeficiency Virus (HIV)-Infected and HIV-Uninfected Pregnant and Postpartum Women: A Longitudinal Cohort Study.

    Science.gov (United States)

    Madhi, Shabir A; Cutland, Clare L; Downs, Sarah; Jones, Stephanie; van Niekerk, Nadia; Simoes, Eric A F; Nunes, Marta C

    2018-05-17

    Limited data exist on the burden of respiratory syncytial virus (RSV) illness among pregnant women, to determine their potential benefit from RSV vaccination. We evaluated the incidence of RSV illness from midpregnancy until 24 weeks postpartum in human immunodeficiency virus (HIV)-uninfected and HIV-infected women and their infants. Mother-infant dyads were enrolled in maternal influenza vaccine efficacy trials. These included 1060 and 1056 HIV-uninfected pregnant women in 2011 and 2012, respectively, 194 HIV-infected pregnant women in 2011, and their infants. Upper respiratory tract samples obtained at illness visits were tested for RSV. The incidence (per 1000 person-months) of RSV illness (n = 43 overall) among HIV-uninfected women was lower in 2011 (1.2; 95% confidence interval [CI], .6-2.2) than in 2012 (4.0; 95% CI, 2.8-5.6). The incidence of RSV illness (n = 5) in HIV-infected women was 3.4 (95% CI, 1.4-8.1). Maternal RSV infection was associated with respiratory symptoms including cough (72.1%), rhinorrhea (39.5%), sore throat (37.2%), and headache (42%), but fever was absent. RSV infection during pregnancy was not associated with adverse pregnancy outcomes. Postpartum, RSV infection in mothers (n = 27) was associated with concurrent infection among 51.9% of their infants and, conversely, 29.8% of mothers investigated within 7 days of their infants having an RSV illness also tested positive for RSV. RSV infection is associated with respiratory illness during pregnancy and postpartum. Vaccination of pregnant women against RSV could benefit the mother, albeit primarily against nonfebrile illness, and her infant. NCT01306669 and NCT01306682.

  15. Adjuvants and the vaccine response to the DS-Cav1-stabilized fusion glycoprotein of respiratory syncytial virus.

    Directory of Open Access Journals (Sweden)

    Mallika Sastry

    Full Text Available Appropriate adjuvant selection may be essential to optimize the potency and to tailor the immune response of subunit vaccines. To induce protective responses against respiratory syncytial virus (RSV-a highly prevalent childhood pathogen without a licensed vaccine-we previously engineered a pre-fusion-stabilized trimeric RSV F (pre-F "DS-Cav1" immunogen, which induced high titer RSV-neutralizing antibodies, in mice and non-human primates, when formulated with adjuvants Poly (I:C and Poly (IC:LC, respectively. To assess the impact of different adjuvants, here we formulated RSV F DS-Cav1 with multiple adjuvants and assessed immune responses. Very high RSV-neutralizing antibody responses (19,006 EC50 were observed in naïve mice immunized with 2 doses of DS-Cav1 adjuvanted with Sigma adjuvant system (SAS, an oil-in-water adjuvant, plus Carbopol; high responses (3658-7108 were observed with DS-Cav1 adjuvanted with Alum, SAS alone, Adjuplex, Poly (I:C and Poly (IC:LC; and moderate responses (1251-2129 were observed with DS-Cav1 adjuvanted with the TLR4 agonist MPLA, Alum plus MPLA or AddaVax. In contrast, DS-Cav1 without adjuvant induced low-level responses (6. A balanced IgG1 and IgG2a (Th2/Th1 immune response was elicited in most of the high to very high response groups (all but Alum and Adjuplex. We also tested the immune response induced by DS-Cav1 in elderly mice with pre-existing DS-Cav1 immunity; we observed that DS-Cav1 adjuvanted with SAS plus Carbopol boosted the response 2-3-fold, whereas DS-Cav1 adjuvanted with alum boosted the response 5-fold. Finally, we tested whether a mixture of ISA 71 VG and Carbopol would enhanced the antibody response in DS-Cav1 immunized calves. While pre-F-stabilized bovine RSV F induced very high titers in mice when adjuvanted with SAS plus Carbopol, the addition of Carbopol to ISA 71 VG did not enhance immune responses in calves. The vaccine response to pre-F-stabilized RSV F is augmented by adjuvant, but the

  16. Association of Age With Risk of Hospitalization for Respiratory Syncytial Virus in Preterm Infants With Chronic Lung Disease.

    Science.gov (United States)

    Winterstein, Almut G; Choi, Yoonyoung; Meissner, H Cody

    2018-02-01

    It is unknown whether the age threshold (≤24 months) for preterm infants with chronic lung disease (CLD) to receive immunoprophylaxis for respiratory syncytial virus (RSV) as currently recommended by American Academy of Pediatrics guidelines correctly identified infants at higher risk for hospitalization for RSV. To determine the age when the risk of hospitalization for RSV among preterm infants with CLD becomes equivalent to the risk for healthy, 1-month-old term infants who do not qualify for immunoprophylaxis. A retrospective cohort study was conducted of 1 018 593 healthy term infants and 5181 preterm infants with CLD using Medicaid billing records (Medicaid Analytic eXtract files) from January 1, 1999, to December 31, 2010, linked to Florida and Texas birth and death certificates. Age-trend discrete time logistic regression models within a survival analysis framework were developed, adjusting for covariates including the use of immunoprophylaxis, to compare the risk of hospitalization of preterm infants (CLD at 3 through 34 months of age with the risk of hospitalization of term infants (37-41 weeks' gestational age) at 1 month of age. Age at which risk of hospitalization for RSV among preterm infants with CLD equals the risk for healthy term infants at age 1 month. The study cohort included 1 018 593 healthy term infants and 5181 preterm infants with CLD; because patients could reenter the cohort for a second or third season, the total study cohort consisted of 1 880 531 healthy term infant-seasons (926 206 girls and 954 325 boys; mean [SD] age at first season entry, 12.6 [9.6] months) and 8680 CLD infant-seasons (3519 girls and 5161 boys; mean [SD] age at first season entry, 15.1 [9.1] months). Among term infants with siblings, the risk of hospitalization for RSV averaged across all covariate strata was 9.0 (95% CI, 8.4-9.6) per 1000 patient season-months at 1 month of age. The risk of hospitalization for RSV among preterm infants with CLD

  17. Respiratory syncytial virus (RSV bronchiolitis: comparative study of RSV groups A and B infected children

    Directory of Open Access Journals (Sweden)

    Selir M. Straliotto

    1994-03-01

    Full Text Available The grouping characteristics of 29 respiratory syncitial virus (RSV present in nasopharyngeal cells collectedfrom hospitalized children with bronchiolitis during the 1990RSVseason in Porto Alegre, RS, were analysed. Twenty-two were grouped as belonging to group A and 7 to group B. Cyanosis, oxigen therapy, cough, lenght of hospitalization and atelectasis were observed to be more frequently found within group B infected children. Other clinical signs and symptoms were similarly found in both groups.Estudos recentes de amostras do vírus respiratório sincicial (VRS usando anticorpos monoclonais distiguiram duas variantes antigênicas, designadas como grupos A e B. Estes grupos foram estudados em 29 secreções de nasofaringe positivas para o VRS, provenientes de crianças hospitalizadas com bronquiolite durante surto de virose por VRS, em Porto Alegre, em 1990. Destas, 22 foram grupadas como pertencentes ao grupo A e 7 ao grupo B. Alguns achados clínicos como cianose, tosse, uso de oxigênio e dias de hospitalização foram mais freqüentemente observados em crianças infectadas coin o grupo B do VRS. Outros sinais e sintomas clínicos foram similarmente encontrados nos 2 grupos.

  18. Human T Lymphocytes Are Permissive for Dengue Virus Replication.

    Science.gov (United States)

    Silveira, Guilherme F; Wowk, Pryscilla F; Cataneo, Allan H D; Dos Santos, Paula F; Delgobo, Murilo; Stimamiglio, Marco A; Lo Sarzi, Maria; Thomazelli, Ana Paula F S; Conchon-Costa, Ivete; Pavanelli, Wander R; Antonelli, Lis R V; Báfica, André; Mansur, Daniel S; Dos Santos, Claudia N Duarte; Bordignon, Juliano

    2018-05-15

    Dengue virus (DV) infection can cause either a self-limiting flu-like disease or a threatening hemorrhage that may evolve to shock and death. A variety of cell types, such as dendritic cells, monocytes, and B cells, can be infected by DV. However, despite the role of T lymphocytes in the control of DV replication, there remains a paucity of information on possible DV-T cell interactions during the disease course. In the present study, we have demonstrated that primary human naive CD4 + and CD8 + T cells are permissive for DV infection. Importantly, both T cell subtypes support viral replication and secrete viable virus particles. DV infection triggers the activation of both CD4 + and CD8 + T lymphocytes, but preactivation of T cells reduces the susceptibility of T cells to DV infection. Interestingly, the cytotoxicity-inducing protein granzyme A is highly secreted by human CD4 + but not CD8 + T cells after exposure to DV in vitro Additionally, using annexin V and polycaspase assays, we have demonstrated that T lymphocytes, in contrast to monocytes, are resistant to DV-induced apoptosis. Strikingly, both CD4 + and CD8 + T cells were found to be infected with DV in acutely infected dengue patients. Together, these results show that T cells are permissive for DV infection in vitro and in vivo , suggesting that this cell population may be a viral reservoir during the acute phase of the disease. IMPORTANCE Infection by dengue virus (DV) causes a flu-like disease that can evolve to severe hemorrhaging and death. T lymphocytes are important cells that regulate antibody secretion by B cells and trigger the death of infected cells. However, little is known about the direct interaction between DV and T lymphocytes. Here, we show that T lymphocytes from healthy donors are susceptible to infection by DV, leading to cell activation. Additionally, T cells seem to be resistant to DV-induced apoptosis, suggesting a potential role as a viral reservoir in humans. Finally, we show

  19. A Polyamide Inhibits Replication of Vesicular Stomatitis Virus by Targeting RNA in the Nucleocapsid

    Energy Technology Data Exchange (ETDEWEB)

    Gumpper, Ryan H.; Li, Weike; Castañeda, Carlos H.; Scuderi, M. José; Bashkin, James K.; Luo, Ming; Dutch, Rebecca Ellis

    2018-02-07

    Polyamides have been shown to bind double-stranded DNA by complementing the curvature of the minor groove and forming various hydrogen bonds with DNA. Several polyamide molecules have been found to have potent antiviral activities against papillomavirus, a double-stranded DNA virus. By analogy, we reason that polyamides may also interact with the structured RNA bound in the nucleocapsid of a negative-strand RNA virus. Vesicular stomatitis virus (VSV) was selected as a prototype virus to test this possibility since its genomic RNA encapsidated in the nucleocapsid forms a structure resembling one strand of an A-form RNA duplex. One polyamide molecule, UMSL1011, was found to inhibit infection of VSV. To confirm that the polyamide targeted the nucleocapsid, a nucleocapsid-like particle (NLP) was incubated with UMSL1011. The encapsidated RNA in the polyamide-treated NLP was protected from thermo-release and digestion by RNase A. UMSL1011 also inhibits viral RNA synthesis in the intracellular activity assay for the viral RNA-dependent RNA polymerase. The crystal structure revealed that UMSL1011 binds the structured RNA in the nucleocapsid. The conclusion of our studies is that the RNA in the nucleocapsid is a viable antiviral target of polyamides. Since the RNA structure in the nucleocapsid is similar in all negative-strand RNA viruses, polyamides may be optimized to target the specific RNA genome of a negative-strand RNA virus, such as respiratory syncytial virus and Ebola virus.

    IMPORTANCENegative-strand RNA viruses (NSVs) include several life-threatening pathogens, such as rabies virus, respiratory syncytial virus, and Ebola virus. There are no effective antiviral drugs against these viruses. Polyamides offer an exceptional opportunity because they may be optimized to target each NSV. Our studies on vesicular stomatitis virus, an NSV, demonstrated that a polyamide molecule could specifically target the viral RNA in the nucleocapsid and inhibit

  20. CT-morphological characterization of respiratory syncytial virus (RSV) pneumonia in immune-compromised adults

    International Nuclear Information System (INIS)

    Mayer, J.L.; Kauczor, H.U.; Lehners, N.; Egerer, G.; Heussel, C.P.

    2014-01-01

    Characterization and follow-up evaluation of chest CT of RSV pneumonia in immune-compromised adults during a seasonal epidemic. Retrospective analysis of 132 chest CT examinations of 51 adult immune-compromised patients (29 m/22f, diameter 58 years) with clinical signs of pneumonia and positive RSV test in winter 2011/2012. Two experienced chest radiologists evaluated the morphology (bronchial wall thickening, tree-in-bud, nodules, halo, ground-glass opacities, consolidations, pleural fluid) of the CT scans by consensus. Pathological findings were in 86 % of the chest CT scans: Areas of ground-glass attenuation in 64 %, consolidations in 56 %, nodules in 55 % (diameter 8 mm in maximal diameter, with halo in 71 %), pleural fluid in 44 % (diameter 2 cm), tree-in-bud in 36 %, bronchial wall thickening in 27 % and more than one morphological finding in 72 %. There were no pathological CT findings in 14 % of patients with clinical symptoms of pneumonia because these patients did not undergo follow-up. Radiological progression was found in 45 % of patients and regression in 33 % in follow-up examinations. In 37 % an additional examination of the paranasal sinuses was performed and showed sinusitis in 63 % of cases. 90 % of the patients had sinusitis as well as pneumonia. In addition to RSV, a further pathogenic agent was found in bronchoalveolar lavage of five patients (Aspergillus spec., herpes simplex virus, Pseudomonas aeruginosa). The most characteristic signs in chest CT scans were at the beginning of pneumonia with nodules and tree-in-bud often combined with bronchial wall thickening. The following CT scans showed characteristic but not pathognomonic chest CT findings of RSV pneumonia. These morphological findings should be recognized seasonally (winter) especially at the beginning of the case of pneumonia. RSV-associated additional sinusitis is probably common and should be noticed.

  1. The V protein of canine distemper virus is required for virus replication in human epithelial cells.

    Directory of Open Access Journals (Sweden)

    Noriyuki Otsuki

    Full Text Available Canine distemper virus (CDV becomes able to use human receptors through a single amino acid substitution in the H protein. In addition, CDV strains possessing an intact C protein replicate well in human epithelial H358 cells. The present study showed that CDV strain 007Lm, which was isolated from lymph node tissue of a dog with distemper, failed to replicate in H358 cells, although it possessed an intact C protein. Sequence analyses suggested that a cysteine-to-tyrosine substitution at position 267 of the V protein caused this growth defect. Analyses using H358 cells constitutively expressing the CDV V protein showed that the V protein with a cysteine, but not that with a tyrosine, at this position effectively blocked the interferon-stimulated signal transduction pathway, and supported virus replication of 007Lm in H358 cells. Thus, the V protein as well as the C protein appears to be functional and essential for CDV replication in human epithelial cells.

  2. A replication-deficient rabies virus vaccine expressing Ebola virus glycoprotein is highly attenuated for neurovirulence

    International Nuclear Information System (INIS)

    Papaneri, Amy B.; Wirblich, Christoph; Cann, Jennifer A.; Cooper, Kurt; Jahrling, Peter B.; Schnell, Matthias J.; Blaney, Joseph E.

    2012-01-01

    We are developing inactivated and live-attenuated rabies virus (RABV) vaccines expressing Ebola virus (EBOV) glycoprotein for use in humans and endangered wildlife, respectively. Here, we further characterize the pathogenesis of the live-attenuated RABV/EBOV vaccine candidates in mice in an effort to define their growth properties and potential for safety. RABV vaccines expressing GP (RV-GP) or a replication-deficient derivative with a deletion of the RABV G gene (RVΔG-GP) are both avirulent after intracerebral inoculation of adult mice. Furthermore, RVΔG-GP is completely avirulent upon intracerebral inoculation of suckling mice unlike parental RABV vaccine or RV-GP. Analysis of RVΔG-GP in the brain by quantitative PCR, determination of virus titer, and immunohistochemistry indicated greatly restricted virus replication. In summary, our findings indicate that RV-GP retains the attenuation phenotype of the live-attenuated RABV vaccine, and RVΔG-GP would appear to be an even safer alternative for use in wildlife or consideration for human use.

  3. CD11c controls herpes simplex virus 1 responses to limit virus replication during primary infection.

    Science.gov (United States)

    Allen, Sariah J; Mott, Kevin R; Chentoufi, Aziz A; BenMohamed, Lbachir; Wechsler, Steven L; Ballantyne, Christie M; Ghiasi, Homayon

    2011-10-01

    CD11c is expressed on the surface of dendritic cells (DCs) and is one of the main markers for identification of DCs. DCs are the effectors of central innate immune responses, but they also affect acquired immune responses to infection. However, how DCs influence the efficacy of adaptive immunity is poorly understood. Here, we show that CD11c(+) DCs negatively orchestrate both adaptive and innate immunity against herpes simplex virus type 1 (HSV-1) ocular infection. The effectiveness and quantity of virus-specific CD8(+) T cell responses are increased in CD11c-deficient animals. In addition, the levels of CD83, CD11b, alpha interferon (IFN-α), and IFN-β, but not IFN-γ, were significantly increased in CD11c-deficient animals. Higher levels of IFN-α, IFN-β, and CD8(+) T cells in the CD11c-deficient mice may have contributed to lower virus replication in the eye and trigeminal ganglia (TG) during the early period of infection than in wild-type mice. However, the absence of CD11c did not influence survival, severity of eye disease, or latency. Our studies provide for the first time evidence that CD11c expression may abrogate the ability to reduce primary virus replication in the eye and TG via higher activities of type 1 interferon and CD8(+) T cell responses.

  4. A replication-deficient rabies virus vaccine expressing Ebola virus glycoprotein is highly attenuated for neurovirulence

    Energy Technology Data Exchange (ETDEWEB)

    Papaneri, Amy B. [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States); Wirblich, Christoph [Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Cann, Jennifer A.; Cooper, Kurt [Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick MD, 21702 (United States); Jahrling, Peter B. [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States); Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick MD, 21702 (United States); Schnell, Matthias J., E-mail: matthias.schnell@jefferson.edu [Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Jefferson Vaccine Center, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Blaney, Joseph E., E-mail: jblaney@niaid.nih.gov [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States)

    2012-12-05

    We are developing inactivated and live-attenuated rabies virus (RABV) vaccines expressing Ebola virus (EBOV) glycoprotein for use in humans and endangered wildlife, respectively. Here, we further characterize the pathogenesis of the live-attenuated RABV/EBOV vaccine candidates in mice in an effort to define their growth properties and potential for safety. RABV vaccines expressing GP (RV-GP) or a replication-deficient derivative with a deletion of the RABV G gene (RV{Delta}G-GP) are both avirulent after intracerebral inoculation of adult mice. Furthermore, RV{Delta}G-GP is completely avirulent upon intracerebral inoculation of suckling mice unlike parental RABV vaccine or RV-GP. Analysis of RV{Delta}G-GP in the brain by quantitative PCR, determination of virus titer, and immunohistochemistry indicated greatly restricted virus replication. In summary, our findings indicate that RV-GP retains the attenuation phenotype of the live-attenuated RABV vaccine, and RV{Delta}G-GP would appear to be an even safer alternative for use in wildlife or consideration for human use.

  5. The Genomic Replication of the Crenarchaeal Virus SIRV2

    DEFF Research Database (Denmark)

    Martinez Alvarez, Laura

    reinitiation events may partially explain the branched topology of the viral replication intermediates. We also analyzed the intracellular location of viral replication, showing the formation of viral peripheral replication centers in SIRV2-infected cells, where viral DNA synthesis and replication...

  6. Inhibition of Mayaro virus replication by cerulenin in Aedes albopictus cells

    International Nuclear Information System (INIS)

    Pereira, H.S.; Rebello, M.A.

    1998-01-01

    The antibiotic cerulenin, an inhibitor of lipid synthesis, was shown to suppress Mayaro virus replication in Aedes albopictus cells at non-cytotoxic doses. Cerulenin blocked the incorporation of [ 3 H]glycerol into lipids when present at anytime post infection. Cerulenin added at the beginning of infection inhibited the synthesis of virus proteins. However, when this antibiotic was added at later stages of infection, it had only a mild effect on the virus protein synthesis. The possibility that cerulenin acts by blocking an initial step in the Mayaro virus replication after virus entry and before late viral translation is discussed. (authors)

  7. Differential association with cellular substructures of pseudorabies virus DNA during early and late phases of replication

    International Nuclear Information System (INIS)

    Ben-Porat, T.; Veach, R.A.; Blankenship, M.L.; Kaplan, A.S.

    1984-01-01

    Pseudorabies virus DNA synthesis can be divided into two phases, early and late, which can be distinguished from each other on the basis of the structures of the replicating DNA. The two types of replicating virus DNA can also be distinguished from each other on the basis of the cellular substructures with which each is associated. Analysis by electron microscopic autoradiography showed that during the first round of replication, nascent virus DNA was found in the vicinity of the nuclear membrane; during later rounds of replication the nascent virus DNA was located centrally within the nucleus. The degree of association of virus DNA synthesized at early and late phases with the nuclear matrix fractions also differed; a larger proportion of late than of early nascent virus DNA was associated with this fraction. While nascent cellular DNA only was associated in significant amounts with the nuclear matrix fraction, a large part (up to 40%) of all the virus DNA remained associated with this fraction. However, no retention of specific virus proteins in this fraction was observed. Except for two virus proteins, which were preferentially extracted from the nuclear matrix, approximately 20% of all virus proteins remained in the nuclear matrix fraction. The large proportion of virus DNA associated with the nuclear fraction indicated that virus DNA may be intimately associated with some proteins

  8. Flock House virus subgenomic RNA3 is replicated and its replication correlates with transactivation of RNA2

    International Nuclear Information System (INIS)

    Eckerle, Lance D.; Albarino, Cesar G.; Ball, L. Andrew.

    2003-01-01

    The nodavirus Flock House virus has a bipartite genome composed of RNAs 1 and 2, which encode the catalytic component of the RNA-dependent RNA polymerase (RdRp) and the capsid protein precursor, respectively. In addition to catalyzing replication of the viral genome, the RdRp also transcribes from RNA1 a subgenomic RNA3, which is both required for and suppressed by RNA2 replication. Here, we show that in the absence of RNA1 replication, FHV RdRp replicated positive-sense RNA3 transcripts fully and copied negative-sense RNA3 transcripts into positive strands. The two nonstructural proteins encoded by RNA3 were dispensable for replication, but sequences in the 3'-terminal 58 nucleotides were required. RNA3 variants that failed to replicate also failed to transactivate RNA2. These results imply that RNA3 is naturally produced both by transcription from RNA1 and by subsequent RNA1-independent replication and that RNA3 replication may be necessary for transactivation of RNA2

  9. Neuraminidase treatment of respiratory syncytial virus-infected cells or virions, but not target cells, enhances cell-cell fusion and infection

    International Nuclear Information System (INIS)

    Barretto, Naina; Hallak, Louay K.; Peeples, Mark E.

    2003-01-01

    Respiratory syncytial virus (RSV) infection of HeLa cells induces fusion, but transient expression of the three viral glycoproteins induces fusion poorly, if at all. We found that neuraminidase treatment of RSV-infected cells to remove sialic acid (SA) increases fusion dramatically and that the same treatment of transiently transfected cells expressing the three viral glycoproteins, or even cells expressing the fusion (F) protein alone, results in easily detectable fusion. Neuraminidase treatment of the effector cells, expressing the viral glycoproteins, enhanced fusion while treatment of the target cells did not. Likewise, infectivity was increased by treating virions with neuraminidase, but not by treating target cells. Reduction of charge repulsion by removal of the negatively charged SA is unlikely to explain this effect, since removal of negative charges from either membrane would reduce charge repulsion. Infection with neuraminidase-treated virus remained heparan-sulfate-dependent, indicating that a novel attachment mechanism is not revealed by SA removal. Interestingly, neuraminidase enhancement of RSV infectivity was less pronounced in a virus expressing both the G and the F glycoproteins, compared to virus expressing only the F glycoprotein, possibly suggesting that the G protein sterically hinders access of the neuraminidase to its fusion-enhancing target

  10. Costs of hospitalization with respiratory syncytial virus illness among children aged <5 years and the financial impact on households in Bangladesh, 2010.

    Science.gov (United States)

    Bhuiyan, Mejbah Uddin; Luby, Stephen P; Alamgir, Nadia Ishrat; Homaira, Nusrat; Sturm-Ramirez, Katharine; Gurley, Emily S; Abedin, Jaynal; Zaman, Rashid Uz; Alamgir, Asm; Rahman, Mahmudur; Ortega-Sanchez, Ismael R; Azziz-Baumgartner, Eduardo

    2017-06-01

    Respiratory syncytial virus (RSV) is the leading cause of acute respiratory illness in young children and results in significant economic burden. There is no vaccine to prevent RSV illness but a number of vaccines are in development. We conducted this study to estimate the costs of severe RSV illness requiring hospitalization among children 50% families borrowed money to meet treatment cost. We estimated that the median direct cost of RSV-associated hospitalization in children aged <5 years in Bangladesh was US$ 10 million (IQR: US$ 7-16 million), the median indirect cost was US$ 3.0 million (IQR: 2-5 million) in 2010. RSV-associated hospitalization among children aged <5 years represents a substantial economic burden in Bangladesh. Affected families frequently incurred considerable out of pocket and indirect costs for treatment that resulted in financial hardship.

  11. Respiratory Syncytial Virus Infection as a Precipitant of Thyroid Storm in a Previously Undiagnosed Case of Graves' Disease in a Prepubertal Girl

    Directory of Open Access Journals (Sweden)

    Charlton RWilliam

    2011-03-01

    Full Text Available Graves' disease is less common in prepubertal than pubertal children, and initial presentation with thyroid storm is rare. We report an 11-year-old prepubertal Hispanic girl who presented with a one-day history of respiratory distress, fever, and dysphagia. She had exophthalmos, a diffuse bilateral goiter and was agitated, tachycardic, and hypertensive. Nasal swab was positive for respiratory syncytial virus (RSV. She was diagnosed with thyroid storm and admitted to the pediatric intensive care unit. While infection is a known precipitant of thyroid storm and RSV is a common pediatric infection, to the best of our knowledge, this is the first reported case of RSV infection apparently precipitating thyroid storm in a prepubertal child.

  12. The acute phase response of haptoglobin and serum amyloid A (SAA) in cattle undergoing experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Heegaard, Peter M. H.; Godson, D.L.; Toussaint, M.J.M.

    2000-01-01

    respiratory syncytial virus (BRSV), analysing the induction of the two most dominant bovine acute phase proteins haptoglobin and serum amyloid A (SAA). Strong and reproducible acute phase responses were detected for both proteins, peaking at around 7-8 days after inoculation of BRSV, while no response...... was seen in mock-inoculated control animals. The serum concentrations reached for SAA and haptoglobin during the BRSV-induced acute phase response were generally the same or higher than previously reported for bacterial infections in calves. The magnitude and the duration of the haptoglobin response...... was found to correlate well with the severity of clinical signs (fever) and with the extent of lung consolidation while SAA responded most rapidly to infection....

  13. Fulminant ecchymosis as the initial manifestation of antiphospholipid syndrome (APS triggered by respiratory syncytial virus (RSV infection: A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Jun Makino

    2017-01-01

    Full Text Available We present a unique and informative instance of respiratory syncytial virus (RSV infection associated with antiphospholipid syndrome (APS, and discuss this case in the context of the literature addressing the immunopathogenesis of APS associated with diverse infections. We describe the case of a 43-year-old man with no significant past medical history who presented with the acute onset of fever, hemoptysis, and extensive bullous, ecchymotic lesions in both lower extremities. Punch biopsy of the lesion demonstrated thrombotic vasculopathy. Further evaluation revealed serum antiphospholipid antibodies as well as a positive RSV PCR in a nasal swab specimen. Clinical manifestations, positive laboratory and pathological findings were strongly suggestive of APS associated with a recent RSV infection. When an infectious etiology is considered for APS, RSV should also be included in the differential diagnosis.

  14. Fulminant ecchymosis as the initial manifestation of antiphospholipid syndrome (APS) triggered by respiratory syncytial virus (RSV) infection: A case report and review of the literature.

    Science.gov (United States)

    Makino, Jun; Koshy, Sanjana; Bajaj, Sonal; Jeong, Young-Gwang; Perlman, David C

    2017-01-01

    We present a unique and informative instance of respiratory syncytial virus (RSV) infection associated with antiphospholipid syndrome (APS), and discuss this case in the context of the literature addressing the immunopathogenesis of APS associated with diverse infections. We describe the case of a 43-year-old man with no significant past medical history who presented with the acute onset of fever, hemoptysis, and extensive bullous, ecchymotic lesions in both lower extremities. Punch biopsy of the lesion demonstrated thrombotic vasculopathy. Further evaluation revealed serum antiphospholipid antibodies as well as a positive RSV PCR in a nasal swab specimen. Clinical manifestations, positive laboratory and pathological findings were strongly suggestive of APS associated with a recent RSV infection. When an infectious etiology is considered for APS, RSV should also be included in the differential diagnosis.

  15. Diagnosis of enzootic pneumonia in Danish cattle: reverse transcription-polymerase chain reaction assay for detection of bovine respiratory syncytial virus in naturally and experimentally infected cattle

    DEFF Research Database (Denmark)

    Larsen, Lars Erik; Tjørnehøj, Kirsten; Viuff, B.

    1999-01-01

    A reverse transcription-polymerase chain reaction (RT-PCR) assay was developed for detection of bovine respiratory syncytial virus (BRSV) in lung tissue of naturally and experimentally infected cattle. Primers were selected from the gene coding the F fusion protein, which is relatively conserved......, in addition, 10 animals that were negative with the ELISA were positive with the RT-PCR assay. These results indicates that the RT-PCR assay can be a sensitive, reliable alternative to conventional diagnostic procedures....... among BRSV isolates. The RT-PCR assay was highly specific, it yielded positive reactions only when performed on BRSV-infected cell cultures or tissues. The detection limit of the RT-PCR assay was assessed as 5 TCID50. BRSV was detected in tissues of the respiratory tract and in the tracheobroncheal...

  16. An evaluation of the emerging interventions against Respiratory Syncytial Virus (RSV-associated acute lower respiratory infections in children

    Directory of Open Access Journals (Sweden)

    Simões Eric AF

    2011-04-01

    Full Text Available Abstract Background Respiratory Syncytial Virus (RSV is the leading cause of acute lower respiratory infections (ALRI in children. It is estimated to cause approximately 33.8 million new episodes of ALRI in children annually, 96% of these occurring in developing countries. It is also estimated to result in about 53,000 to 199,000 deaths annually in young children. Currently there are several vaccine and immunoprophylaxis candidates against RSV in the developmental phase targeting active and passive immunization. Methods We used a modified CHNRI methodology for setting priorities in health research investments. This was done in two stages. In Stage I, we systematically reviewed the literature related to emerging vaccines against RSV relevant to 12 criteria of interest. In Stage II, we conducted an expert opinion exercise by inviting 20 experts (leading basic scientists, international public health researchers, international policy makers and representatives of pharmaceutical companies. The policy makers and industry representatives accepted our invitation on the condition of anonymity, due to the sensitive nature of their involvement in such exercises. They answered questions from the CHNRI framework and their “collective optimism” towards each criterion was documented on a scale from 0 to 100%. Results In the case of candidate vaccines for active immunization of infants against RSV, the experts expressed very low levels of optimism for low product cost, affordability and low cost of development; moderate levels of optimism regarding the criteria of answerability, likelihood of efficacy, deliverability, sustainability and acceptance to end users for the interventions; and high levels of optimism regarding impact on equity and acceptance to health workers. While considering the candidate vaccines targeting pregnant women, the panel expressed low levels of optimism for low product cost, affordability, answerability and low development cost

  17. An evaluation of the emerging interventions against Respiratory Syncytial Virus (RSV)-associated acute lower respiratory infections in children.

    Science.gov (United States)

    Nair, Harish; Verma, Vasundhara R; Theodoratou, Evropi; Zgaga, Lina; Huda, Tanvir; Simões, Eric A F; Wright, Peter F; Rudan, Igor; Campbell, Harry

    2011-04-13

    Respiratory Syncytial Virus (RSV) is the leading cause of acute lower respiratory infections (ALRI) in children. It is estimated to cause approximately 33.8 million new episodes of ALRI in children annually, 96% of these occurring in developing countries. It is also estimated to result in about 53,000 to 199,000 deaths annually in young children. Currently there are several vaccine and immunoprophylaxis candidates against RSV in the developmental phase targeting active and passive immunization. We used a modified CHNRI methodology for setting priorities in health research investments. This was done in two stages. In Stage I, we systematically reviewed the literature related to emerging vaccines against RSV relevant to 12 criteria of interest. In Stage II, we conducted an expert opinion exercise by inviting 20 experts (leading basic scientists, international public health researchers, international policy makers and representatives of pharmaceutical companies). The policy makers and industry representatives accepted our invitation on the condition of anonymity, due to the sensitive nature of their involvement in such exercises. They answered questions from the CHNRI framework and their "collective optimism" towards each criterion was documented on a scale from 0 to 100%. In the case of candidate vaccines for active immunization of infants against RSV, the experts expressed very low levels of optimism for low product cost, affordability and low cost of development; moderate levels of optimism regarding the criteria of answerability, likelihood of efficacy, deliverability, sustainability and acceptance to end users for the interventions; and high levels of optimism regarding impact on equity and acceptance to health workers. While considering the candidate vaccines targeting pregnant women, the panel expressed low levels of optimism for low product cost, affordability, answerability and low development cost; moderate levels of optimism for likelihood of efficacy

  18. Inhibition of herpesvirus and influenza virus replication by blocking polymerase subunit interactions.

    Science.gov (United States)

    Palù, Giorgio; Loregian, Arianna

    2013-09-01

    Protein-protein interactions (PPIs) play a key role in many biological processes, including virus replication in the host cell. Since most of the PPIs are functionally essential, a possible strategy to inhibit virus replication is based on the disruption of viral protein complexes by peptides or small molecules that interfere with subunit interactions. In particular, an attractive target for antiviral drugs is the binding between the subunits of essential viral enzymes. This review describes the development of new antiviral compounds that inhibit herpesvirus and influenza virus replication by blocking interactions between subunit proteins of their polymerase complexes. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Absence of Association between Cord Specific Antibody Levels and Severe Respiratory Syncytial Virus (RSV) Disease in Early Infants: A Case Control Study from Coastal Kenya.

    Science.gov (United States)

    Nyiro, Joyce Uchi; Sande, Charles Jumba; Mutunga, Martin; Kiyuka, Patience Kerubo; Munywoki, Patrick Kioo; Scott, John Anthony G; Nokes, David James

    2016-01-01

    The target group for severe respiratory syncytial virus (RSV) disease prevention is infants under 6 months of age. Vaccine boosting of antibody titres in pregnant mothers could protect these young infants from severe respiratory syncytial virus (RSV) associated disease. Quantifying protective levels of RSV-specific maternal antibody at birth would inform vaccine development. A case control study nested in a birth cohort (2002-07) was conducted in Kilifi, Kenya; where 30 hospitalised cases of RSV-associated severe disease were matched to 60 controls. Participants had a cord blood and 2 subsequent 3-monthly blood samples assayed for RSV-specific neutralising antibody by the plaque reduction neutralisation test (PRNT). Two sample paired t test and conditional logistic regression were used in analyses of log2PRNT titres. The mean RSV log2PRNT titre at birth for cases and controls were not significantly different (P = 0.4) and remained so on age-stratification. Cord blood PRNT titres showed considerable overlap between cases and controls. The odds of RSV disease decreased with increase in log2PRNT cord blood titre. There was a 30% reduction in RSV disease per unit increase in log2PRNT titre (disease. Cord antibody levels show wide variation with considerable overlap between cases and controls. It is likely that, there are additional factors to specific PRNT antibody levels which determine susceptibility to severe RSV disease. In addition, higher levels of neutralizing antibody beyond the normal range may be required for protection; which it is hoped can be achieved by a maternal RSV vaccine.

  20. Up-regulation of serum periostin and squamous cell carcinoma antigen levels in infants with acute bronchitis due to respiratory syncytial virus

    Directory of Open Access Journals (Sweden)

    Hiroaki Nakamura

    2018-04-01

    Full Text Available Background: Periostin and squamous cell carcinoma antigen (SCCA are involved in the pathogenesis of asthma. Acute bronchitis due to respiratory syncytial virus (RSV infection during infancy exhibits an asthma-like pathogenesis, suggesting that it may be associated with the subsequent development of asthma. However, the mechanism by which RSV infection leads to development of asthma has not yet been fully elucidated. Methods: Infants younger than 36 months were enrolled and classified into three groups. Group I included patients hospitalized with RSV-induced bronchitis. These patients were further stratified into two sub-groups according to whether the criteria for the modified Asthma Predictive Index (mAPI had been met: Group I consisted of mAPI (+ and mAPI (− patients; Group II included patients with food allergy as a positive control group; and Group III included children with no allergy as a negative control group. Serum periostin and SCCA levels were measured in the groups. This study was registered as a clinical trial (UMIN000012339. Results: We enrolled 14 subjects in Group I mAPI (+, 22 in Group I mAPI (−, 18 in Group II, and 18 in Group III. In Group I, the serum periostin and SCCA levels were significantly higher during the acute phase compared with the recovery phase. However, no significant differences were found between Group I mAPI (+ and mAPI (−. Conclusions: The serum periostin and SCCA levels increased during acute RSV bronchitis. Both periostin and SCCA may play a role in the pathogenesis of acute bronchitis due to RSV. Keywords: Infants, Periostin, Respiratory syncytial virus, Squamous cell carcinoma antigen, T-helper 2 cell cytokines

  1. Respiratory Syncytial Virus (RSV)

    Science.gov (United States)

    ... Careers Archives Health Topics Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal care Is it safe? Labor & ... Report Cards Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal care Is it safe? Labor & ...

  2. Replication and transmission of H9N2 influenza viruses in ferrets: evaluation of pandemic potential.

    Directory of Open Access Journals (Sweden)

    Hongquan Wan

    2008-08-01

    Full Text Available H9N2 avian influenza A viruses are endemic in poultry of many Eurasian countries and have caused repeated human infections in Asia since 1998. To evaluate the potential threat of H9N2 viruses to humans, we investigated the replication and transmission efficiency of H9N2 viruses in the ferret model. Five wild-type (WT H9N2 viruses, isolated from different avian species from 1988 through 2003, were tested in vivo and found to replicate in ferrets. However these viruses achieved mild peak viral titers in nasal washes when compared to those observed with a human H3N2 virus. Two of these H9N2 viruses transmitted to direct contact ferrets, however no aerosol transmission was detected in the virus displaying the most efficient direct contact transmission. A leucine (Leu residue at amino acid position 226 in the hemagglutinin (HA receptor-binding site (RBS, responsible for human virus-like receptor specificity, was found to be important for the transmission of the H9N2 viruses in ferrets. In addition, an H9N2 avian-human reassortant virus, which contains the surface glycoprotein genes from an H9N2 virus and the six internal genes of a human H3N2 virus, showed enhanced replication and efficient transmission to direct contacts. Although no aerosol transmission was observed, the virus replicated in multiple respiratory tissues and induced clinical signs similar to those observed with the parental human H3N2 virus. Our results suggest that the establishment and prevalence of H9N2 viruses in poultry pose a significant threat for humans.

  3. Hepatitis A virus infection suppresses hepatitis C virus replication and may lead to clearance of HCV.

    Science.gov (United States)

    Deterding, Katja; Tegtmeyer, Björn; Cornberg, Markus; Hadem, Johannes; Potthoff, Andrej; Böker, Klaus H W; Tillmann, Hans L; Manns, Michael P; Wedemeyer, Heiner

    2006-12-01

    The significance of hepatitis A virus (HAV) super-infection in patients with chronic hepatitis C had been a matter of debate. While some studies suggested an incidence of fulminant hepatitis A of up to 35%, this could not be confirmed by others. We identified 17 anti-HCV-positive patients with acute hepatitis A from a cohort of 3170 anti-HCV-positive patients recruited at a single center over a period of 12 years. Importantly, none of the anti-HCV-positive patients had a fulminant course of hepatitis A. HCV-RNA was detected by PCR in 84% of the anti-HCV-positive/anti-HAV-IgM-negative patients but only in 65% of anti-HCV-positive patients with acute hepatitis A (p=0.03), indicating suppression of HCV replication during hepatitis A. Previous HAV infection had no effect on HCV replication. After recovery from hepatitis A, an increased HCV replication could be demonstrated for 6 out of 9 patients with serial quantitative HCV-RNA values available while 2 patients remained HCV-RNA negative after clearance of HAV throughout follow-up of at least 2 years. HAV super-infection is associated with decreased HCV-RNA replication which may lead to recovery from HCV in some individuals. Fulminant hepatitis A is not frequent in patients with chronic hepatitis C recruited at a tertiary referral center.

  4. Wolbachia wStri Blocks Zika Virus Growth at Two Independent Stages of Viral Replication.

    Science.gov (United States)

    Schultz, M J; Tan, A L; Gray, C N; Isern, S; Michael, S F; Frydman, H M; Connor, J H

    2018-05-22

    Mosquito-transmitted viruses are spread globally and present a great risk to human health. Among the many approaches investigated to limit the diseases caused by these viruses are attempts to make mosquitos resistant to virus infection. Coinfection of mosquitos with the bacterium Wolbachia pipientis from supergroup A is a recent strategy employed to reduce the capacity for major vectors in the Aedes mosquito genus to transmit viruses, including dengue virus (DENV), Chikungunya virus (CHIKV), and Zika virus (ZIKV). Recently, a supergroup B Wolbachia w Stri, isolated from Laodelphax striatellus , was shown to inhibit multiple lineages of ZIKV in Aedes albopictus cells. Here, we show that w Stri blocks the growth of positive-sense RNA viruses DENV, CHIKV, ZIKV, and yellow fever virus by greater than 99.9%. w Stri presence did not affect the growth of the negative-sense RNA viruses LaCrosse virus or vesicular stomatitis virus. Investigation of the stages of the ZIKV life cycle inhibited by w Stri identified two distinct blocks in viral replication. We found a reduction of ZIKV entry into w Stri-infected cells. This was partially rescued by the addition of a cholesterol-lipid supplement. Independent of entry, transfected viral genome was unable to replicate in Wolbachia -infected cells. RNA transfection and metabolic labeling studies suggested that this replication defect is at the level of RNA translation, where we saw a 66% reduction in mosquito protein synthesis in w Stri-infected cells. This study's findings increase the potential for application of w Stri to block additional arboviruses and also identify specific blocks in viral infection caused by Wolbachia coinfection. IMPORTANCE Dengue, Zika, and yellow fever viruses are mosquito-transmitted diseases that have spread throughout the world, causing millions of infections and thousands of deaths each year. Existing programs that seek to contain these diseases through elimination of the mosquito population have so

  5. Replication of swine and human influenza viruses in juvenile and layer turkey hens.

    Science.gov (United States)

    Ali, Ahmed; Yassine, Hadi; Awe, Olusegun O; Ibrahim, Mahmoud; Saif, Yehia M; Lee, Chang-Won

    2013-04-12

    Since the first reported isolation of swine influenza viruses (SIVs) in turkeys in the 1980s, transmission of SIVs to turkeys was frequently documented. Recently, the 2009 pandemic H1N1 virus, that was thought to be of swine origin, was detected in turkeys with a severe drop in egg production. In this study, we assessed the infectivity of different mammalian influenza viruses including swine, pandemic H1N1 and seasonal human influenza viruses in both juvenile and layer turkeys. In addition, we investigated the potential influenza virus dissemination in the semen of experimentally infected turkey toms. Results showed that all mammalian origin influenza viruses tested can infect turkeys. SIVs were detected in respiratory and digestive tracts of both juvenile and layer turkeys. Variations in replication efficiencies among SIVs were observed especially in the reproductive tract of layer turkeys. Compared to SIVs, limited replication of seasonal human H1N1 and no detectable replication of recent human-like swine H1N2, pandemic H1N1 and seasonal human H3N2 viruses was noticed. All birds seroconverted to all tested viruses regardless of their replication level. In turkey toms, we were able to detect swine H3N2 virus in semen and reproductive tract of infected toms by real-time RT-PCR although virus isolation was not successful. These data suggest that turkey hens could be affected by diverse influenza strains especially SIVs. Moreover, the differences in the replication efficiency we demonstrated among SIVs and between SIV and human influenza viruses in layer turkeys suggest a possible use of turkeys as an animal model to study host tropism and pathogenesis of influenza viruses. Our results also indicate a potential risk of venereal transmission of influenza viruses in turkeys. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Assessing Human Immunodeficiency Virus Type 1 Tropism: Comparison of Assays Using Replication-Competent Virus versus Plasma-Derived Pseudotyped Virions ▿

    Science.gov (United States)

    Hosoya, Noriaki; Su, Zhaohui; Wilkin, Timothy; Gulick, Roy M.; Flexner, Charles; Hughes, Michael D.; Skolnik, Paul R.; Giguel, Françoise; Greaves, Wayne L.; Coakley, Eoin; Kuritzkes, Daniel R.

    2009-01-01

    Detection of CXCR4-using human immunodeficiency virus by the Trofile assay was compared to that by assays using virus isolates or replication-competent recombinants. Concordance with the Trofile assay was good, but assays using replicating viruses did not increase substantially the ability to detect the presence of CXCR4-using virus. PMID:19494074

  7. Cutthroat trout virus as a surrogate in vitro infection model for testing inhibitors of hepatitis E virus replication

    Science.gov (United States)

    Debing, Yannick; Winton, James; Neyts, Johan; Dallmeier, Kai

    2013-01-01

    Hepatitis E virus (HEV) is one of the most important causes of acute hepatitis worldwide. Although most infections are self-limiting, mortality is particularly high in pregnant women. Chronic infections can occur in transplant and other immune-compromised patients. Successful treatment of chronic hepatitis E has been reported with ribavirin and pegylated interferon-alpha, however severe side effects were observed. We employed the cutthroat trout virus (CTV), a non-pathogenic fish virus with remarkable similarities to HEV, as a potential surrogate for HEV and established an antiviral assay against this virus using the Chinook salmon embryo (CHSE-214) cell line. Ribavirin and the respective trout interferon were found to efficiently inhibit CTV replication. Other known broad-spectrum inhibitors of RNA virus replication such as the nucleoside analog 2′-C-methylcytidine resulted only in a moderate antiviral activity. In its natural fish host, CTV levels largely fluctuate during the reproductive cycle with the virus detected mainly during spawning. We wondered whether this aspect of CTV infection may serve as a surrogate model for the peculiar pathogenesis of HEV in pregnant women. To that end the effect of three sex steroids on in vitro CTV replication was evaluated. Whereas progesterone resulted in marked inhibition of virus replication, testosterone and 17β-estradiol stimulated viral growth. Our data thus indicate that CTV may serve as a surrogate model for HEV, both for antiviral experiments and studies on the replication biology of the Hepeviridae.

  8. Adeno-associated virus type 2 enhances goose parvovirus replication in embryonated goose eggs

    International Nuclear Information System (INIS)

    Malkinson, Mertyn; Winocour, Ernest

    2005-01-01

    The autonomous goose parvovirus (GPV) and the human helper-dependent adeno-associated virus type 2 (AAV2) share a high degree of homology. To determine if this evolutionary relationship has a biological impact, we studied viral replication in human 293 cells and in embryonated goose eggs coinfected with both viruses. Similar experiments were performed with the minute virus of mice (MVM), an autonomous murine parvovirus with less homology to AAV2. In human 293 cells, both GPV and MVM augmented AAV2 replication. In contrast, AAV2 markedly enhanced GPV replication in embryonated goose eggs under conditions where a similar effect was not observed with MVM. AAV2 did not replicate in embryonated goose eggs and AAV2 inactivated by UV-irradiation also enhanced GPV replication. To our knowledge, this is the first report that a human helper-dependent member of the Parvoviridae can provide helper activity for an autonomous parvovirus in a natural host

  9. Clinical and epidemiological aspects related to the detection of adenovirus or respiratory syncytial virus in infants hospitalized for acute lower respiratory tract infection

    Directory of Open Access Journals (Sweden)

    Eduardo A. Ferone

    2014-01-01

    Full Text Available OBJECTIVE: To characterize and compare clinical, epidemiological, and laboratory aspects ofinfants with acute lower respiratory infection (ALRI associated with the detection of adenovirus(ADV or respiratory syncytial virus (RSV. METHODS: A preliminary respiratory infection surveillance study collected samples of nasopharyngeal aspirate (NPA for viral research, linked to the completion of a standard protocol, from children younger than two years admitted to a university hospital with ALRI, between March of 2008 and August of 2011. Polymerase chain reaction (PCR was used for eight viruses: ADV, RSV, metapneumovirus, Parainfluenza 1, 2, and 3, and Influenza A and B. Cases with NPA collectedduring the first 24 hours of admission, negative results of blood culture, and exclusive detection of ADV (Gadv group or RSV (Grsv group were selected for comparisons. RESULTS: The preliminary study included collection of 1,121 samples of NPA, 813 collected in thefirst 24 hours of admission, of which 50.3% were positive for at least one virus; RSV was identifiedin 27.3% of cases surveyed, and ADV was identified in 15.8%. Among the aspects analyzed inthe Gadv (n = 58 and Grsv (n = 134 groups, the following are noteworthy: the higher meanage, more frequent prescription of antibiotics, and the highest median of total white blood cellcount and C-reactive protein values in Gadv. CONCLUSIONS: PCR can detect persistent/latent forms of ADV, an aspect to be considered wheninterpreting results. Additional studies with quantitative diagnostic techniques could elucidatethe importance of the high frequency observed.

  10. Three-Dimensional Architecture and Biogenesis of Membrane Structures Associated with Plant Virus Replication

    Directory of Open Access Journals (Sweden)

    Xuejiao Jin

    2018-01-01

    Full Text Available Positive-sense (+ RNA viruses represent the most abundant group of viruses and are dependent on the host cell machinery to replicate. One remarkable feature that occurs after (+ RNA virus entry into cells is the remodeling of host endomembranes, leading to the formation of viral replication factories. Recently, rapid progress in three-dimensional (3D imaging technologies, such as electron tomography (ET and focused ion beam-scanning electron microscopy (FIB-SEM, has enabled researchers to visualize the novel membrane structures induced by viruses at high resolution. These 3D imaging technologies provide new mechanistic insights into the viral infection cycle. In this review, we summarize the latest reports on the cellular remodeling that occurs during plant virus infection; in particular, we focus on studies that provide 3D architectural information on viral replication factories. We also outline the mechanisms underlying the formation of these membranous structures and discuss possible future research directions.

  11. In Vivo Replication and Pathogenesis of Vesicular Stomatitis Virus Recombinant M40 Containing Ebola Virus L-Domain Sequences

    Directory of Open Access Journals (Sweden)

    Takashi Irie

    2012-01-01

    Full Text Available The M40 VSV recombinant was engineered to contain overlapping PTAP and PPxY L-domain motifs and flanking residues from the VP40 protein of Ebola virus. Replication of M40 in cell culture is virtually indistinguishable from that of control viruses. However, the presence of the Ebola PTAP motif in the M40 recombinant enabled this virus to interact with and recruit host Tsg101, which was packaged into M40 virions. In this brief report, we compared replication and the pathogenic profiles of M40 and the parental virus M51R in mice to determine whether the presence of the Ebola L-domains and flanking residues altered in vivo characteristics of the virus. Overall, the in vivo characteristics of M40 were similar to those of the parental M51R virus, indicating that the Ebola sequences did not alter pathogenesis of VSV in this small animal model of infection.

  12. Influenza B virus M2 protein can functionally replace its influenza A virus counterpart in promoting virus replication

    International Nuclear Information System (INIS)

    Wanitchang, Asawin; Wongthida, Phonphimon; Jongkaewwattana, Anan

    2016-01-01

    The M2 protein (AM2 and BM2) of influenza A and B viruses function as a proton channel essential for viral replication. They also carry a cytoplasmic tail whose functions are not fully delineated. It is currently unknown whether these proteins could be replaced functionally in a viral context. Here, we generated single-cycle influenza A viruses (scIAV-ΔHA) carrying various M2-2A-mCherry constructs in the segment 4 (HA) and evaluated their growth in complementing cells. Intriguingly, the scIAV-ΔHA carrying AM2 and that bearing BM2 grew comparably well in MDCK-HA cells. Furthermore, while the virus carrying chimeric B-AM2 in which the BM2 transmembrane fused with the AM2 cytoplasmic tail produced robust infection, the one bearing the AM2 transmembrane fused with the BM2 cytoplasmic tail (A-BM2) exhibited severely impaired growth. Altogether, we demonstrate that AM2 and BM2 are functionally interchangeable and underscore the role of compatibility between transmembrane and cytoplasmic tail of the M2 protein. -- Highlights: •Flu A M2 protein (AM2) can be functionally replaced by that of Flu B (BM2). •Both AM2 and BM2 with extended cytoplasmic tail are functional. •Compatibility between the ion channel and the cytoplasmic tail is critical for M2 function. •M2 with higher ion channel activity may augment influenza virus replication.

  13. Influenza B virus M2 protein can functionally replace its influenza A virus counterpart in promoting virus replication

    Energy Technology Data Exchange (ETDEWEB)

    Wanitchang, Asawin; Wongthida, Phonphimon; Jongkaewwattana, Anan, E-mail: anan.jon@biotec.or.th

    2016-11-15

    The M2 protein (AM2 and BM2) of influenza A and B viruses function as a proton channel essential for viral replication. They also carry a cytoplasmic tail whose functions are not fully delineated. It is currently unknown whether these proteins could be replaced functionally in a viral context. Here, we generated single-cycle influenza A viruses (scIAV-ΔHA) carrying various M2-2A-mCherry constructs in the segment 4 (HA) and evaluated their growth in complementing cells. Intriguingly, the scIAV-ΔHA carrying AM2 and that bearing BM2 grew comparably well in MDCK-HA cells. Furthermore, while the virus carrying chimeric B-AM2 in which the BM2 transmembrane fused with the AM2 cytoplasmic tail produced robust infection, the one bearing the AM2 transmembrane fused with the BM2 cytoplasmic tail (A-BM2) exhibited severely impaired growth. Altogether, we demonstrate that AM2 and BM2 are functionally interchangeable and underscore the role of compatibility between transmembrane and cytoplasmic tail of the M2 protein. -- Highlights: •Flu A M2 protein (AM2) can be functionally replaced by that of Flu B (BM2). •Both AM2 and BM2 with extended cytoplasmic tail are functional. •Compatibility between the ion channel and the cytoplasmic tail is critical for M2 function. •M2 with higher ion channel activity may augment influenza virus replication.

  14. An upstream open reading frame modulates ebola virus polymerase translation and virus replication.

    Directory of Open Access Journals (Sweden)

    Reed S Shabman

    2013-01-01

    Full Text Available Ebolaviruses, highly lethal zoonotic pathogens, possess longer genomes than most other non-segmented negative-strand RNA viruses due in part to long 5' and 3' untranslated regions (UTRs present in the seven viral transcriptional units. To date, specific functions have not been assigned to these UTRs. With reporter assays, we demonstrated that the Zaire ebolavirus (EBOV 5'-UTRs lack internal ribosomal entry site function. However, the 5'-UTRs do differentially regulate cap-dependent translation when placed upstream of a GFP reporter gene. Most dramatically, the 5'-UTR derived from the viral polymerase (L mRNA strongly suppressed translation of GFP compared to a β-actin 5'-UTR. The L 5'-UTR is one of four viral genes to possess upstream AUGs (uAUGs, and ablation of each uAUG enhanced translation of the primary ORF (pORF, most dramatically in the case of the L 5'-UTR. The L uAUG was sufficient to initiate translation, is surrounded by a "weak" Kozak sequence and suppressed pORF translation in a position-dependent manner. Under conditions where eIF2α was phosphorylated, the presence of the uORF maintained translation of the L pORF, indicating that the uORF modulates L translation in response to cellular stress. To directly address the role of the L uAUG in virus replication, a recombinant EBOV was generated in which the L uAUG was mutated to UCG. Strikingly, mutating two nucleotides outside of previously-defined protein coding and cis-acting regulatory sequences attenuated virus growth to titers 10-100-fold lower than a wild-type virus in Vero and A549 cells. The mutant virus also exhibited decreased viral RNA synthesis as early as 6 hours post-infection and enhanced sensitivity to the stress inducer thapsigargin. Cumulatively, these data identify novel mechanisms by which EBOV regulates its polymerase expression, demonstrate their relevance to virus replication and identify a potential therapeutic target.

  15. Molecular cloning of osteoma-inducing replication-competent murine leukemia viruses from the RFB osteoma virus stock

    DEFF Research Database (Denmark)

    Pedersen, Lene; Behnisch, Werner; Schmidt, Jörg

    1992-01-01

    We report the molecular cloning of two replication-competent osteoma-inducing murine leukemia viruses from the RFB osteoma virus stock (M. P. Finkel, C. A. Reilly, Jr., B. O. Biskis, and I. L. Greco, p. 353-366, in C. H. G. Price and F. G. M. Ross, ed., Bone--Certain Aspects of Neoplasia, 1973......). Like the original RFB osteoma virus stock, viruses derived from the molecular RFB clones induced multiple osteomas in mice of the CBA/Ca strain. The cloned RFB viruses were indistinguishable by restriction enzyme analysis and by nucleotide sequence analysis of their long-terminal-repeat regions...

  16. Enhanced replication of UV-damaged Simian virus 40 DNA in carcinogen-treated mammalian cells

    International Nuclear Information System (INIS)

    Maga, J.A.

    1983-01-01

    The replication of UV-damaged Simian virus 40 (SV40) in carcinogen-treated monkey cells has been studied to elucidate the mechanism of carcinogen-enhanced reactivation. Carcinogen enhanced reactivation is the observed increase in UV-irradiated virus survival in host cells treated with low doses of carcinogen compared to UV-irradiated virus survival in untreated hosts. Carcinogen treatment of monkey kidney cells with either N-acetoxy-2-acetylaminofluorene (AAAF) or UV radiation leads to an enhanced capacity to replicate UV-damaged virus during the first round of infection. To further define the mechanism leading to enhanced replication, a detailed biochemical analysis of replication intermediates in carcinogen-treated cells was performed. Several conclusions can be drawn. First enhanced replication can be observed in the first four rounds of replication after UV irradiation of viral templates. The second major finding is that the relaxed circular intermediate model proposed for the replication of UV-damaged templates in untreated cells appears valid for replication of UV-damaged templates in carcinogen-treated cells. Possible mechanisms and the supporting evidence are discussed and future experiments outlined

  17. Phosphatidic acid produced by phospholipase D promotes RNA replication of a plant RNA virus.

    Directory of Open Access Journals (Sweden)

    Kiwamu Hyodo

    2015-05-01

    Full Text Available Eukaryotic positive-strand RNA [(+RNA] viruses are intracellular obligate parasites replicate using the membrane-bound replicase complexes that contain multiple viral and host components. To replicate, (+RNA viruses exploit host resources and modify host metabolism and membrane organization. Phospholipase D (PLD is a phosphatidylcholine- and phosphatidylethanolamine-hydrolyzing enzyme that catalyzes the production of phosphatidic acid (PA, a lipid second messenger that modulates diverse intracellular signaling in various organisms. PA is normally present in small amounts (less than 1% of total phospholipids, but rapidly and transiently accumulates in lipid bilayers in response to different environmental cues such as biotic and abiotic stresses in plants. However, the precise functions of PLD and PA remain unknown. Here, we report the roles of PLD and PA in genomic RNA replication of a plant (+RNA virus, Red clover necrotic mosaic virus (RCNMV. We found that RCNMV RNA replication complexes formed in Nicotiana benthamiana contained PLDα and PLDβ. Gene-silencing and pharmacological inhibition approaches showed that PLDs and PLDs-derived PA are required for viral RNA replication. Consistent with this, exogenous application of PA enhanced viral RNA replication in plant cells and plant-derived cell-free extracts. We also found that a viral auxiliary replication protein bound to PA in vitro, and that the amount of PA increased in RCNMV-infected plant leaves. Together, our findings suggest that RCNMV hijacks host PA-producing enzymes to replicate.

  18. Genes and sequences involved in the replication of cowpea mosaic virus RNAs

    NARCIS (Netherlands)

    Eggen, R.

    1989-01-01

    The aim of the studies described in this thesis was to gain more insight in the complex molecular mechanisms underlying the RNA replication of the cowpea mosaic virus genome. Previously the replication of CPMV RNA has been examined extensively with crude membrane fractions prepared from

  19. Bicyclams, selective antagonists of the human chemokine receptor CXCR4, potently inhibit feline immunodeficiency virus replication

    NARCIS (Netherlands)

    Horzinek, M.C.; Egberink, H.F.; Clercq, E. de; Vliet, A.L.W. van; Balzarini, J.; Bridger, G.J.; Henson, G.; Schols, D.

    1999-01-01

    Bicyclams are low-molecular-weight anti-human immunodeficiency virus (HIV) agents that have been shown to act as potent and selective CXC chemokine receptor 4 (CXCR4) antagonists. Here, we demonstrate that bicyclams are potent inhibitors of feline immunodeficiency virus (FIV) replication when

  20. A chimeric measles virus with a lentiviral envelope replicates exclusively in CD4+/CCR5+ cells

    International Nuclear Information System (INIS)

    Mourez, Thomas; Mesel-Lemoine, Mariana; Combredet, Chantal; Najburg, Valerie; Cayet, Nadege; Tangy, Frederic

    2011-01-01

    We generated a replicating chimeric measles virus in which the hemagglutinin and fusion surface glycoproteins were replaced with the gp160 envelope glycoprotein of simian immunodeficiency virus (SIVmac239). Based on a previously cloned live-attenuated Schwarz vaccine strain of measles virus (MV), this chimera was rescued at high titers using reverse genetics in CD4+ target cells. Cytopathic effect consisted in the presence of large cell aggregates evolving to form syncytia, as observed during SIV infection. The morphology of the chimeric virus was identical to that of the parent MV particles. The presence of SIV gp160 as the only envelope protein on chimeric particles surface altered the cell tropism of the new virus from CD46+ to CD4+ cells. Used as an HIV candidate vaccine, this MV/SIVenv chimeric virus would mimic transient HIV-like infection, benefiting both from HIV-like tropism and the capacity of MV to replicate in dendritic cells, macrophages and lymphocytes.

  1. Newcastle disease virus triggers autophagy in U251 glioma cells to enhance virus replication.

    Science.gov (United States)

    Meng, Chunchun; Zhou, Zhizhi; Jiang, Ke; Yu, Shengqing; Jia, Lijun; Wu, Yantao; Liu, Yanqing; Meng, Songshu; Ding, Chan

    2012-06-01

    Newcastle disease virus (NDV) can replicate in tumor cells and induce apoptosis in late stages of infection. However, the interaction between NDV and cells in early stages of infection is not well understood. Here, we report that, shortly after infection, NDV triggers the formation of autophagosomes in U251 glioma cells, as demonstrated by an increased number of double-membrane vesicles, GFP-microtubule-associated protein 1 light chain 3 (GFP-LC3) a dot formations, and elevated production of LC3II. Moreover, modulation of NDV-induced autophagy by rapamycin, chloroquine or small interfering RNAs targeting the genes critical for autophagosome formation (Atg5 and Beclin-1) affects virus production, indicating that autophagy may be utilized by NDV to facilitate its own production. Furthermore, the class III phosphatidylinositol 3-kinase (PI3K)/Beclin-1 pathway plays a role in NDV-induced autophagy and virus production. Collectively, our data provide a unique example of a paramyxovirus that uses autophagy to enhance its production.

  2. Respiratory syncytial virus infection induces higher Toll-like receptor-3 expression and TNF-α production than human metapneumovirus infection.

    Directory of Open Access Journals (Sweden)

    Ying Dou

    Full Text Available Respiratory syncytial virus (RSV and human metapneumovirus (hMPV are common causes of respiratory infections in children. Diseases caused by hMPV are generally considered to be less severe than those caused by RSV; the underlying mechanisms, however, remain unknown. In the present study, the expressions of TLRs in airway epithelial cells and lungs of BALB/c mice infected by hMPV or RSV were measured in an attempt to explore the differences in the airway inflammation caused by the two viruses. Our results demonstrate that both hMPV and RSV infection upregulated the expressions of TLRs and inflammatory cytokines. Specifically, the TLR3 expression was revealed to be elevated in vitro and in mouse lungs. IFN-α produced by A549 cells after RSV or hMPV infection remained undistinguishable, whereas production of TNF-α was significantly higher after RSV infection than hMPV infection either in the presence or absence of Poly I:C. This study provides a clue that more severe clinical syndrome of RSV infection may be due to the greater magnitude of induction of airway inflammation by RSV involving TLR3 activation and production of TNF-α.

  3. Structural characterization of respiratory syncytial virus fusion inhibitor escape mutants: homology model of the F protein and a syncytium formation assay

    International Nuclear Information System (INIS)

    Morton, Craig J.; Cameron, Rachel; Lawrence, Lynne J.; Lin Bo; Lowe, Melinda; Luttick, Angela; Mason, Anthony; McKimm-Breschkin, Jenny; Parker, Michael W.; Ryan, Jane; Smout, Michael; Sullivan, Jayne; Tucker, Simon P.; Young, Paul R.

    2003-01-01

    Respiratory syncytial virus (RSV) is a ubiquitous human pathogen and the leading cause of lower respiratory tract infections in infants. Infection of cells and subsequent formation of syncytia occur through membrane fusion mediated by the RSV fusion protein (RSV-F). A novel in vitro assay of recombinant RSV-F function has been devised and used to characterize a number of escape mutants for three known inhibitors of RSV-F that have been isolated. Homology modeling of the RSV-F structure has been carried out on the basis of a chimera derived from the crystal structures of the RSV-F core and a fragment from the orthologous fusion protein from Newcastle disease virus (NDV). The structure correlates well with the appearance of RSV-F in electron micrographs, and the residues identified as contributing to specific binding sites for several monoclonal antibodies are arranged in appropriate solvent-accessible clusters. The positions of the characterized resistance mutants in the model structure identify two promising regions for the design of fusion inhibitors

  4. Epidemiology of respiratory syncytial virus-associated acute lower respiratory tract infection hospitalizations among HIV-infected and HIV-uninfected South African children, 2010-2011.

    Science.gov (United States)

    Moyes, Jocelyn; Cohen, Cheryl; Pretorius, Marthi; Groome, Michelle; von Gottberg, Anne; Wolter, Nicole; Walaza, Sibongile; Haffejee, Sumayya; Chhagan, Meera; Naby, Fathima; Cohen, Adam L; Tempia, Stefano; Kahn, Kathleen; Dawood, Halima; Venter, Marietjie; Madhi, Shabir A

    2013-12-15

    There are limited data on respiratory syncytial virus (RSV) infection among children in settings with a high prevalence of human immunodeficiency virus (HIV). We studied the epidemiology of RSV-associated acute lower respiratory tract infection (ALRTI) hospitalizations among HIV-infected and HIV-uninfected children in South Africa. Children aged infection among HIV-infected and uninfected children were examined. The relative risk of hospitalization in HIV-infected and HIV-uninfected children was calculated in 1 site with population denominators. Of 4489 participants, 4293 (96%) were tested for RSV, of whom 1157 (27%) tested positive. With adjustment for age, HIV-infected children had a 3-5-fold increased risk of hospitalization with RSV-associated ALRTI (2010 relative risk, 5.6; [95% confidence interval (CI), 4.5-6.4]; 2011 relative risk, 3.1 [95% CI, 2.6-3.6]). On multivariable analysis, HIV-infected children with RSV-associated ALRTI had higher odds of death (adjusted odds ratio. 31.1; 95% CI, 5.4-179.8) and hospitalization for >5 days (adjusted odds ratio, 4.0; 95% CI, 1.5-10.6) than HIV-uninfected children. HIV-infected children have a higher risk of hospitalization with RSV-associated ALRTI and a poorer outcome than HIV-uninfected children. These children should be targeted for interventions aimed at preventing severe RSV disease.

  5. The Central Conserved Region (CCR) of Respiratory Syncytial Virus (RSV) G Protein Modulates Host miRNA Expression and Alters the Cellular Response to Infection.

    Science.gov (United States)

    Bakre, Abhijeet A; Harcourt, Jennifer L; Haynes, Lia M; Anderson, Larry J; Tripp, Ralph A

    2017-07-03

    Respiratory Syncytial Virus (RSV) infects respiratory epithelial cells and deregulates host gene expression by many mechanisms including expression of RSV G protein (RSV G). RSV G protein encodes a central conserved region (CCR) containing a CX3C motif that functions as a fractalkine mimic. Disruption of the CX3C motif (a.a. 182-186) located in the CCR of the G protein has been shown to affect G protein function in vitro and the severity of RSV disease pathogenesis in vivo. We show that infection of polarized Calu3 respiratory cells with recombinant RSV having point mutations in Cys173 and 176 (C173/176S) (rA2-GC12), or Cys186 (C186S) (rA2-GC4) is associated with a decline in the integrity of polarized Calu-3 cultures and decreased virus production. This is accompanied with downregulation of miRNAs let-7f and miR-24 and upregulation of interferon lambda (IFNλ), a primary antiviral cytokine for RSV in rA2-GC12/rA2-GC4 infected cells. These results suggest that residues in the cysteine noose region of RSV G protein can modulate IFN λ expression accompanied by downregulation of miRNAs, and are important for RSV G protein function and targeting.

  6. Enhanced replication of herpes simplex virus type 1 in human cells

    International Nuclear Information System (INIS)

    Miller, C.S.; Smith, K.O.

    1991-01-01

    The effects of DNA-damaging agents on the replication of herpes simplex virus type 1 (HSV-1) were assessed in vitro. Monolayers of human lung fibroblast cell lines were exposed to DNA-damaging agents (methyl methanesulfonate [MMS], methyl methanethiosulfonate [MMTS], ultraviolet light [UV], or gamma radiation [GR]) at specific intervals, before or after inoculation with low levels of HSV-1. The ability of cell monolayers to support HSV-1 replication was measured by direct plaque assay and was compared with that of untreated control samples. In this system, monolayers of different cell lines infected with identical HSV-1 strains demonstrated dissimilar levels of recovery of the infectious virus. Exposure of DNA-repair-competent cell cultures to DNA-damaging agents produced time-dependent enhanced virus replication. Treatment with agent before virus inoculation significantly (p less than 0.025) increased the number of plaques by 10 to 68%, compared with untreated control cultures, while treatment with agent after virus adsorption significantly increased (p less than 0.025) the number of plaques by 7 to 15%. In a parallel series of experiments, cells deficient in DNA repair (xeroderma pigmentosum) failed to support enhanced virus replication. These results suggest that after exposure to DNA-damaging agents, fibroblasts competent in DNA repair amplify the replication of HSV-1, and that DNA-repair mechanisms that act on a variety of chromosomal lesions may be involved in the repair and biological activation of HSV-1 genomes

  7. Clinical characteristics and viral load of respiratory syncytial virus and human metapneumovirus in children hospitaled for acute lower respiratory tract infection.

    Science.gov (United States)

    Yan, Xiao-Li; Li, Yu-Ning; Tang, Yi-Jie; Xie, Zhi-Ping; Gao, Han-Chun; Yang, Xue-Mei; Li, Yu-Mei; Liu, Li-Jun; Duan, Zhao-Jun

    2017-04-01

    Respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) are two common viral pathogens in acute lower respiratory tract infections (ALRTI). However, the association of viral load with clinical characteristics is not well-defined in ALRTI. To explore the correlation between viral load and clinical characteristics of RSV and HMPV in children hospitalized for ALRTI in Lanzhou, China. Three hundred and eighty-seven children hospitalized for ALRTI were enrolled. Nasopharyngeal aspirates (NPAs) were sampled from each children. Real-time PCR was used to screen RSV, HMPV, and twelve additional respiratory viruses. Bronchiolitis was the leading diagnoses both in RSV and HMPV positive patients. A significantly greater frequency of wheezing (52% vs. 33.52%, P = 0.000) was noted in RSV positive and negative patients. The RSV viral load was significant higher in children aged infections (P = 0.000). No difference was found in the clinical features of HMPV positive and negative patients. The HMPV viral load had no correlation with any clinical characteristics. The incidences of severe disease were similar between single infection and coinfection for the two viruses (RSV, P = 0.221; HMPV, P = 0.764) and there has no statistical significance between severity and viral load (P = 0.166 and P = 0.721). Bronchiolitis is the most common disease caused by RSV and HMPV. High viral load or co-infection may be associated with some symptoms but neither has a significant impact on disease severity for the two viruses. J. Med. Virol. 89:589-597, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. The Tat protein of human immunodeficiency virus-1 enhances hepatitis C virus replication through interferon gamma-inducible protein-10

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    Qu Jing

    2012-04-01

    Full Text Available Abstract Background Co-infection with human immunodeficiency virus-1 (HIV-1 and hepatitis C virus (HCV is associated with faster progression of liver disease and an increase in HCV persistence. However, the mechanism by which HIV-1 accelerates the progression of HCV liver disease remains unknown. Results HIV-1/HCV co-infection is associated with increased expression of interferon gamma-induced protein-10 (IP-10 mRNA in peripheral blood mononuclear cells (PBMCs. HCV RNA levels were higher in PBMCs of patients with HIV-1/HCV co-infection than in patients with HCV mono-infection. HIV-1 Tat and IP-10 activated HCV replication in a time-dependent manner, and HIV-1 Tat induced IP-10 production. In addition, the effect of HIV-1 Tat on HCV replication was blocked by anti-IP-10 monoclonal antibody, demonstrating that the effect of HIV-1 Tat on HCV replication depends on IP-10. Taken together, these results suggest that HIV-1 Tat protein activates HCV replication by upregulating IP-10 production. Conclusions HIV-1/HCV co-infection is associated with increased expression of IP-10 mRNA and replication of HCV RNA. Furthermore, both HIV-1 Tat and IP-10 activate HCV replication. HIV-1 Tat activates HCV replication by upregulating IP-10 production. These results expand our understanding of HIV-1 in HCV replication and the mechanism involved in the regulation of HCV replication mediated by HIV-1 during co-infection.

  9. Structural analysis of respiratory syncytial virus reveals the position of M2-1 between the matrix protein and the ribonucleoprotein complex.

    Science.gov (United States)

    Kiss, Gabriella; Holl, Jens M; Williams, Grant M; Alonas, Eric; Vanover, Daryll; Lifland, Aaron W; Gudheti, Manasa; Guerrero-Ferreira, Ricardo C; Nair, Vinod; Yi, Hong; Graham, Barney S; Santangelo, Philip J; Wright, Elizabeth R

    2014-07-01

    Respiratory syncytial virus (RSV), a member of the Paramyxoviridae family of nonsegmented, negative-sense, single-stranded RNA genome viruses, is a leading cause of lower respiratory tract infections in infants, young children, and the elderly or immunocompromised. There are many open questions regarding the processes that regulate human RSV (hRSV) assembly and budding. Here, using cryo-electron tomography, we identified virus particles that were spherical, filamentous, and asymmetric in structure, all within the same virus preparation. The three particle morphologies maintained a similar organization of the surface glycoproteins, matrix protein (M), M2-1, and the ribonucleoprotein (RNP). RNP filaments were traced in three dimensions (3D), and their total length was calculated. The measurements revealed the inclusion of multiple full-length genome copies per particle. RNP was associated with the membrane whenever the M layer was present. The amount of M coverage ranged from 24% to 86% in the different morphologies. Using fluorescence light microscopy (fLM), direct stochastic optical reconstruction microscopy (dSTORM), and a proximity ligation assay (PLA), we provide evidence illustrating that M2-1 is located between RNP and M in isolated viral particles. In addition, regular spacing of the M2-1 densities was resolved when hRSV viruses were imaged using Zernike phase contrast (ZPC) cryo-electron tomography. Our studies provide a more complete characterization of the hRSV virion structure and substantiation that M and M2-1 regulate virus organization. hRSV is a leading cause of lower respiratory tract infections in infants and young children as well as elderly or immunocompromised individuals. We used cryo-electron tomography and Zernike phase contrast cryo-electron tomography to visualize populations of purified hRSV in 3D. We observed the three distinct morphologies, spherical, filamentous, and asymmetric, which maintained comparable organizational profiles

  10. Hepatitis C virus resistance to broadly neutralizing antibodies measured using replication-competent virus and pseudoparticles.

    Science.gov (United States)

    Wasilewski, Lisa N; Ray, Stuart C; Bailey, Justin R

    2016-11-01

    A better understanding of natural variation in neutralization resistance and fitness of diverse hepatitis C virus (HCV) envelope (E1E2) variants will be critical to guide rational development of an HCV vaccine. This work has been hindered by inadequate genetic diversity in viral panels and by a lack of standardization of HCV entry assays. Neutralization assays generally use lentiviral pseudoparticles expressing HCV envelope proteins (HCVpp) or chimeric full-length viruses that are replication competent in cell culture (HCVcc). There have been few systematic comparisons of specific infectivities of E1E2-matched HCVcc and HCVpp, and to our knowledge, neutralization of E1E2-matched HCVpp and HCVcc has never been compared using a diverse panel of human broadly neutralizing monoclonal antibodies (bNAbs) targeting distinct epitopes. Here, we describe an efficient method for introduction of naturally occurring E1E2 genes into a full-length HCV genome, producing replication-competent chimeric HCVcc. We generated diverse panels of E1E2-matched HCVcc and HCVpp and measured the entry-mediating fitness of E1E2 variants using the two systems. We also compared neutralization of E1E2-matched HCVcc and HCVpp by a diverse panel of human bNAbs targeting epitopes across E1E2. We found no correlation between specific infectivities of E1E2-matched HCVcc versus HCVpp, but found a very strong positive correlation between relative neutralization resistance of these same E1E2-matched HCVcc and HCVpp variants. These results suggest that quantitative comparisons of neutralization resistance of E1E2 variants can be made with confidence using either HCVcc or HCVpp, allowing the use of either or both systems to maximize diversity of neutralization panels.

  11. The place of viruses in biology in light of the metabolism- versus-replication-first debate.

    Science.gov (United States)

    López-García, Purificación

    2012-01-01

    The last decade has seen a revival of old virocentric ideas. These concepts are heterogeneous, extending from proposals that consider viruses functionally as living beings and/or as descendants of viral lineages that preceded cell evolution to other claims that consider viruses and/or some viral families a fourth domain of life. While the debates about whether viruses are alive or not and whether some virus-like replicators preceded the first cells fall under the long-lasting dichotomous view on the nature and origin of life (metabolism- versus replication-first), the claim that some giant viruses form a fourth domain in an organismal tree of life is not consistent with current evidence and can be falsified.

  12. Influenza Virus Induces Inflammatory Response in Mouse Primary Cortical Neurons with Limited Viral Replication

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    Gefei Wang

    2016-01-01

    Full Text Available Unlike stereotypical neurotropic viruses, influenza A viruses have been detected in the brain tissues of human and animal models. To investigate the interaction between neurons and influenza A viruses, mouse cortical neurons were isolated, infected with human H1N1 influenza virus, and then examined for the production of various inflammatory molecules involved in immune response. We found that replication of the influenza virus in neurons was limited, although early viral transcription was not affected. Virus-induced neuron viability decreased at 6 h postinfection (p.i. but increased at 24 h p.i. depending upon the viral strain. Virus-induced apoptosis and cytopathy in primary cortical neurons were not apparent at 24 h p.i. The mRNA levels of inflammatory cytokines, chemokines, and type I interferons were upregulated at 6 h and 24 h p.i. These results indicate that the influenza virus induces inflammatory response in mouse primary cortical neurons with limited viral replication. The cytokines released in viral infection-induced neuroinflammation might play critical roles in influenza encephalopathy, rather than in viral replication-induced cytopathy.

  13. Dynamic remodeling of lipids coincides with dengue virus replication in the midgut of Aedes aegypti mosquitoes.

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    Nunya Chotiwan

    2018-02-01

    Full Text Available We describe the first comprehensive analysis of the midgut metabolome of Aedes aegypti, the primary mosquito vector for arboviruses such as dengue, Zika, chikungunya and yellow fever viruses. Transmission of these viruses depends on their ability to infect, replicate and disseminate from several tissues in the mosquito vector. The metabolic environments within these tissues play crucial roles in these processes. Since these viruses are enveloped, viral replication, assembly and release occur on cellular membranes primed through the manipulation of host metabolism. Interference with this virus infection-induced metabolic environment is detrimental to viral replication in human and mosquito cell culture models. Here we present the first insight into the metabolic environment induced during arbovirus replication in Aedes aegypti. Using high-resolution mass spectrometry, we have analyzed the temporal metabolic perturbations that occur following dengue virus infection of the midgut tissue. This is the primary site of infection and replication, preceding systemic viral dissemination and transmission. We identified metabolites that exhibited a dynamic-profile across early-, mid- and late-infection time points. We observed a marked increase in the lipid content. An increase in glycerophospholipids, sphingolipids and fatty acyls was coincident with the kinetics of viral replication. Elevation of glycerolipid levels suggested a diversion of resources during infection from energy storage to synthetic pathways. Elevated levels of acyl-carnitines were observed, signaling disruptions in mitochondrial function and possible diversion of energy production. A central hub in the sphingolipid pathway that influenced dihydroceramide to ceramide ratios was identified as critical for the virus life cycle. This study also resulted in the first reconstruction of the sphingolipid pathway in Aedes aegypti. Given conservation in the replication mechanisms of several

  14. Dynamic remodeling of lipids coincides with dengue virus replication in the midgut of Aedes aegypti mosquitoes.

    Science.gov (United States)

    Chotiwan, Nunya; Andre, Barbara G; Sanchez-Vargas, Irma; Islam, M Nurul; Grabowski, Jeffrey M; Hopf-Jannasch, Amber; Gough, Erik; Nakayasu, Ernesto; Blair, Carol D; Belisle, John T; Hill, Catherine A; Kuhn, Richard J; Perera, Rushika

    2018-02-01

    We describe the first comprehensive analysis of the midgut metabolome of Aedes aegypti, the primary mosquito vector for arboviruses such as dengue, Zika, chikungunya and yellow fever viruses. Transmission of these viruses depends on their ability to infect, replicate and disseminate from several tissues in the mosquito vector. The metabolic environments within these tissues play crucial roles in these processes. Since these viruses are enveloped, viral replication, assembly and release occur on cellular membranes primed through the manipulation of host metabolism. Interference with this virus infection-induced metabolic environment is detrimental to viral replication in human and mosquito cell culture models. Here we present the first insight into the metabolic environment induced during arbovirus replication in Aedes aegypti. Using high-resolution mass spectrometry, we have analyzed the temporal metabolic perturbations that occur following dengue virus infection of the midgut tissue. This is the primary site of infection and replication, preceding systemic viral dissemination and transmission. We identified metabolites that exhibited a dynamic-profile across early-, mid- and late-infection time points. We observed a marked increase in the lipid content. An increase in glycerophospholipids, sphingolipids and fatty acyls was coincident with the kinetics of viral replication. Elevation of glycerolipid levels suggested a diversion of resources during infection from energy storage to synthetic pathways. Elevated levels of acyl-carnitines were observed, signaling disruptions in mitochondrial function and possible diversion of energy production. A central hub in the sphingolipid pathway that influenced dihydroceramide to ceramide ratios was identified as critical for the virus life cycle. This study also resulted in the first reconstruction of the sphingolipid pathway in Aedes aegypti. Given conservation in the replication mechanisms of several flaviviruses transmitted

  15. Accessory genes confer a high replication rate to virulent feline immunodeficiency virus.

    Science.gov (United States)

    Troyer, Ryan M; Thompson, Jesse; Elder, John H; VandeWoude, Sue

    2013-07-01

    Feline immunodeficiency virus (FIV) is a lentivirus that causes AIDS in domestic cats, similar to human immunodeficiency virus (HIV)/AIDS in humans. The FIV accessory protein Vif abrogates the inhibition of infection by cat APOBEC3 restriction factors. FIV also encodes a multifunctional OrfA accessory protein that has characteristics similar to HIV Tat, Vpu, Vpr, and Nef. To examine the role of vif and orfA accessory genes in FIV replication and pathogenicity, we generated chimeras between two FIV molecular clones with divergent disease potentials: a highly pathogenic isolate that replicates rapidly in vitro and is associated with significant immunopathology in vivo, FIV-C36 (referred to here as high-virulence FIV [HV-FIV]), and a less-pathogenic strain, FIV-PPR (referred to here as low-virulence FIV [LV-FIV]). Using PCR-driven overlap extension, we produced viruses in which vif, orfA, or both genes from virulent HV-FIV replaced equivalent genes in LV-FIV. The generation of these chimeras is more straightforward in FIV than in primate lentiviruses, since FIV accessory gene open reading frames have very little overlap with other genes. All three chimeric viruses exhibited increased replication kinetics in vitro compared to the replication kinetics of LV-FIV. Chimeras containing HV-Vif or Vif/OrfA had replication rates equivalent to those of the virulent HV-FIV parental virus. Furthermore, small interfering RNA knockdown of feline APOBEC3 genes resulted in equalization of replication rates between LV-FIV and LV-FIV encoding HV-FIV Vif. These findings demonstrate that Vif-APOBEC interactions play a key role in controlling the replication and pathogenicity of this immunodeficiency-inducing virus in its native host species and that accessory genes act as mediators of lentiviral strain-specific virulence.

  16. Complete replication of hepatitis B virus and hepatitis C virus in a newly developed hepatoma cell line.

    Science.gov (United States)

    Yang, Darong; Zuo, Chaohui; Wang, Xiaohong; Meng, Xianghe; Xue, Binbin; Liu, Nianli; Yu, Rong; Qin, Yuwen; Gao, Yimin; Wang, Qiuping; Hu, Jun; Wang, Ling; Zhou, Zebin; Liu, Bing; Tan, Deming; Guan, Yang; Zhu, Haizhen

    2014-04-01

    The absence of a robust cell culture system for hepatitis B virus (HBV) and hepatitis C virus (HCV) infection has limited the analysis of the virus lifecycle and drug discovery. We have established a hepatoma cell line, HLCZ01, the first cell line, to the authors' knowledge, supporting the entire lifecycle of both HBV and HCV. HBV surface antigen (HBsAg)-positive particles can be observed in the supernatant and the lumen of the endoplasmic reticulum of the cells via electron microscopy. Interestingly, HBV and HCV clinical isolates propagate in HLCZ01 cells. Both viruses replicate in the cells without evidence of overt interference. HBV and HCV entry are blocked by antibodies against HBsAg and human CD81, respectively, and the replication of HBV and HCV is inhibited by antivirals. HLCZ01 cells mount an innate immune response to virus infection. The cell line provides a powerful tool for exploring the mechanisms of virus entry and replication and the interaction between host and virus, facilitating the development of novel antiviral agents and vaccines.

  17. Inhibition of influenza virus replication by targeting broad host cell pathways.

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    Isabelle Marois

    Full Text Available Antivirals that are currently used to treat influenza virus infections target components of the virus which can mutate rapidly. Consequently, there has been an increase in the number of resistant strains to one or many antivirals in recent years. Here we compared the antiviral effects of lysosomotropic alkalinizing agents (LAAs and calcium modulators (CMs, which interfere with crucial events in the influenza virus replication cycle, against avian, swine, and human viruses of different subtypes in MDCK cells. We observed that treatment with LAAs, CMs, or a combination of both, significantly inhibited viral replication. Moreover, the drugs were effective even when they were administered 8 h after infection. Finally, analysis of the expression of viral acidic polymerase (PA revealed that both drugs classes interfered with early events in the viral replication cycle. This study demonstrates that targeting broad host cellular pathways can be an efficient strategy to inhibit influenza replication. Furthermore, it provides an interesting avenue for drug development where resistance by the virus might be reduced since the virus is not targeted directly.

  18. Cutthroat trout virus as a surrogate in vitro infection model for testing inhibitors of hepatitis E virus replication.

    Science.gov (United States)

    Debing, Yannick; Winton, James; Neyts, Johan; Dallmeier, Kai

    2013-10-01

    Hepatitis E virus (HEV) is one of the most important causes of acute hepatitis worldwide. Although most infections are self-limiting, mortality is particularly high in pregnant women. Chronic infections can occur in transplant and other immune-compromised patients. Successful treatment of chronic hepatitis E has been reported with ribavirin and pegylated interferon-alpha, however severe side effects were observed. We employed the cutthroat trout virus (CTV), a non-pathogenic fish virus with remarkable similarities to HEV, as a potential surrogate for HEV and established an antiviral assay against this virus using the Chinook salmon embryo (CHSE-214) cell line. Ribavirin and the respective trout interferon were found to efficiently inhibit CTV replication. Other known broad-spectrum inhibitors of RNA virus replication such as the nucleoside analog 2'-C-methylcytidine resulted only in a moderate antiviral activity. In its natural fish host, CTV levels largely fluctuate during the reproductive cycle with the virus detected mainly during spawning. We wondered whether this aspect of CTV infection may serve as a surrogate model for the peculiar pathogenesis of HEV in pregnant women. To that end the effect of three sex steroids on in vitro CTV replication was evaluated. Whereas progesterone resulted in marked inhibition of virus replication, testosterone and 17β-estradiol stimulated viral growth. Our data thus indicate that CTV may serve as a surrogate model for HEV, both for antiviral experiments and studies on the replication biology of the Hepeviridae. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Evaluation of the minimal replication time of Cauliflower mosaic virus in different hosts

    International Nuclear Information System (INIS)

    Khelifa, Mounia; Masse, Delphine; Blanc, Stephane; Drucker, Martin

    2010-01-01

    Though the duration of a single round of replication is an important biological parameter, it has been determined for only few viruses. Here, this parameter was determined for Cauliflower mosaic virus (CaMV) in transfected protoplasts from different hosts: the highly susceptible Arabidopsis and turnip, and Nicotiana benthamiana, where CaMV accumulates only slowly. Four methods of differing sensitivity were employed: labelling of (1) progeny DNA and (2) capsid protein, (3) immunocapture PCR,, and (4) progeny-specific PCR. The first progeny virus was detected about 21 h after transfection. This value was confirmed by all methods, indicating that our estimate was not biased by the sensitivity of the detection method, and approximated the actual time required for one round of CaMV replication. Unexpectedly, the replication kinetics were similar in the three hosts; suggesting that slow accumulation of CaMV in Nicotiana plants is determined by non-optimal interactions in other steps of the infection cycle.

  20. The cell biology of Tobacco mosaic virus replication and movement

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    Chengke eLiu

    2013-02-01

    Full Text Available Successful systemic infection of a plant by Tobacco mosaic virus (TMV requires three processes that repeat over time: initial establishment and accumulation in invaded cells, intercellular movement and systemic transport. Accumulation and intercellular movement of TMV necessarily involves intracellular transport by complexes containing virus and host proteins and virus RNA during a dynamic process that can be visualized. Multiple membranes appear to assist TMV accumulation, while membranes, microfilaments and microtubules appear to assist TMV movement. Here we review cell biological studies that describe TMV-membrane, -cytoskeleton and -other host protein interactions which influence virus accumulation and movement in leaves and callus tissue. The importance of understanding the developmental phase of the infection in relationship to the observed virus-membrane or -host protein interaction is emphasized. Utilizing the latest observations of TMV-membrane and -host protein interactions within our evolving understanding of the infection ontogeny, a model for TMV accumulation and intracellular spread in a cell biological context is provided.

  1. Zika Virus RNA Replication and Persistence in Brain and Placental Tissue

    Science.gov (United States)

    Rabeneck, Demi B.; Martines, Roosecelis B.; Reagan-Steiner, Sarah; Ermias, Yokabed; Estetter, Lindsey B.C.; Suzuki, Tadaki; Ritter, Jana; Keating, M. Kelly; Hale, Gillian; Gary, Joy; Muehlenbachs, Atis; Lambert, Amy; Lanciotti, Robert; Oduyebo, Titilope; Meaney-Delman, Dana; Bolaños, Fernando; Saad, Edgar Alberto Parra; Shieh, Wun-Ju; Zaki, Sherif R.

    2017-01-01

    Zika virus is causally linked with congenital microcephaly and may be associated with pregnancy loss. However, the mechanisms of Zika virus intrauterine transmission and replication and its tropism and persistence in tissues are poorly understood. We tested tissues from 52 case-patients: 8 infants with microcephaly who died and 44 women suspected of being infected with Zika virus during pregnancy. By reverse transcription PCR, tissues from 32 (62%) case-patients (brains from 8 infants with microcephaly and placental/fetal tissues from 24 women) were positive for Zika virus. In situ hybridization localized replicative Zika virus RNA in brains of 7 infants and in placentas of 9 women who had pregnancy losses during the first or second trimester. These findings demonstrate that Zika virus replicates and persists in fetal brains and placentas, providing direct evidence of its association with microcephaly. Tissue-based reverse transcription PCR extends the time frame of Zika virus detection in congenital and pregnancy-associated infections. PMID:27959260

  2. Association between the level of antibodies in bulk tank milk and bovine respiratory syncytial virus exposure in the herd.

    Science.gov (United States)

    Klem, T B; Tollersrud, T; Osterås, O; Stokstad, M

    2014-07-12

    Antibody levels in bulk tank milk (BTM) against bovine respiratory syncytial virus (BRSV) are used to classify BRSV status of herds. The aim of this study was to investigate how these levels correspond with the time at which the herds were infected. Bulk tank milk, individual milk and serum samples from cows and young stock were investigated using an indirect ELISA. Screenings of BTM from 89 dairy herds during two winter seasons revealed a prevalence of positive herds from 82 per cent to 85 per cent. Eleven herds showed a marked increase in antibody levels between two screenings, indicating new infection. However, two of these herds had been free from BRSV for the last five to seven years. Two newly infected herds were monitored for four years and did not appear to get reinfected. Surprisingly, the BTM antibody levels in these herds remained high throughout the study period, but fluctuated significantly. This shows that the levels of antibodies in BTM can remain high for several years, even in herds where reinfection does not occur. BTM serology is a useful tool in the monitoring of infectious diseases in dairy herds, but has limitations as a diagnostic tool for BRSV infections. British Veterinary Association.

  3. Differences in viral load among human respiratory syncytial virus genotypes in hospitalized children with severe acute respiratory infections in the Philippines.

    Science.gov (United States)

    Kadji, Francois Marie Ngako; Okamoto, Michiko; Furuse, Yuki; Tamaki, Raita; Suzuki, Akira; Lirio, Irene; Dapat, Clyde; Malasao, Rungnapa; Saito, Mariko; Pedrera-Rico, Gay Anne Granada; Tallo, Veronica; Lupisan, Socorro; Saito, Mayuko; Oshitani, Hitoshi

    2016-06-27

    Human respiratory syncytial virus (HRSV) is a leading viral etiologic agent of pediatric lower respiratory infections, including bronchiolitis and pneumonia. Two antigenic subgroups, HRSV-A and B, each contain several genotypes. While viral load may vary among HRSV genotypes and affect the clinical course of disease, data are scarce regarding the actual differences among genotypes. Therefore, this study estimated and compared viral load among NA1 and ON1 genotypes of HRSV-A and BA9 of HRSV-B. ON1 is a newly emerged genotype with a 72-nucleotide duplication in the G gene as observed previously with BA genotypes in HRSV-B. Children <5 years of age with an initial diagnosis of severe or very severe pneumonia at a hospital in the Philippines from September 2012 to December 2013 were enrolled. HRSV genotypes were determined and the viral load measured from nasopharyngeal swabs (NPS). The viral load of HRSV genotype NA1 were significantly higher than those of ON1 and BA9. Regression analysis showed that both genotype NA1 and younger age were significantly associated with high HRSV viral load. The viral load of NA1 was higher than that of ON1 and BA9 in NPS samples. HRSV genotypes may be associated with HRSV viral load. The reasons and clinical impacts of these differences in viral load among HRSV genotypes require further evaluation.

  4. Genetic variability in G2 and F2 region between biological clones of human respiratory syncytial virus with or without host immune selection pressure

    Directory of Open Access Journals (Sweden)

    Claudia Trigo Pedroso Moraes

    2015-02-01

    Full Text Available Human respiratory syncytial virus (HRSV is an important respiratory pathogens among children between zero-five years old. Host immunity and viral genetic variability are important factors that can make vaccine production difficult. In this work, differences between biological clones of HRSV were detected in clinical samples in the absence and presence of serum collected from children in the convalescent phase of the illness and from their biological mothers. Viral clones were selected by plaque assay in the absence and presence of serum and nucleotide sequences of the G2 and F2 genes of HRSV biological clones were compared. One non-synonymous mutation was found in the F gene (Ile5Asn in one clone of an HRSV-B sample and one non-synonymous mutation was found in the G gene (Ser291Pro in four clones of the same HRSV-B sample. Only one of these clones was obtained after treatment with the child's serum. In addition, some synonymous mutations were determined in two clones of the HRSV-A samples. In conclusion, it is possible that minor sequences could be selected by host antibodies contributing to the HRSV evolutionary process, hampering the development of an effective vaccine, since we verify the same codon alteration in absence and presence of human sera in individual clones of BR-85 sample.

  5. Genetic variability in G2 and F2 region between biological clones of human respiratory syncytial virus with or without host immune selection pressure.

    Science.gov (United States)

    Moraes, Claudia Trigo Pedroso; Oliveira, Danielle Bruna Leal; Campos, Angelica Cristine Almeida; Bosso, Patricia Alves; Lima, Hildener Nogueira; Stewien, Klaus Eberhard; Gilio, Alfredo Elias; Vieira, Sandra Elisabete; Botosso, Viviane Fongaro; Durigon, Edison Luiz

    2015-02-01

    Human respiratory syncytial virus (HRSV) is an important respiratory pathogens among children between zero-five years old. Host immunity and viral genetic variability are important factors that can make vaccine production difficult. In this work, differences between biological clones of HRSV were detected in clinical samples in the absence and presence of serum collected from children in the convalescent phase of the illness and from their biological mothers. Viral clones were selected by plaque assay in the absence and presence of serum and nucleotide sequences of the G2 and F2 genes of HRSV biological clones were compared. One non-synonymous mutation was found in the F gene (Ile5Asn) in one clone of an HRSV-B sample and one non-synonymous mutation was found in the G gene (Ser291Pro) in four clones of the same HRSV-B sample. Only one of these clones was obtained after treatment with the child's serum. In addition, some synonymous mutations were determined in two clones of the HRSV-A samples. In conclusion, it is possible that minor sequences could be selected by host antibodies contributing to the HRSV evolutionary process, hampering the development of an effective vaccine, since we verify the same codon alteration in absence and presence of human sera in individual clones of BR-85 sample.

  6. Duration of secretory IgM and IgA antibodies to respiratory syncytial virus in a community study in Guinea-Bissau

    DEFF Research Database (Denmark)

    Stensballe, L G; Kofoed, P E; Nante, E J

    2000-01-01

    Respiratory syncytial virus (RSV) is probably the single major cause of lower respiratory infection (LRI) among infants worldwide. Its relative importance may be underestimated, as the diagnosis is based on antigen detection and antigen may only be detectable in the early phase of infection. We...... phase of infection. A secondary response may be more likely in children with low IgM responses in the acute phase (RR = 2.08 (95% confidence interval (CI) 0.92-4.70)). The IgA response was highest on days 28 and 42 after antigen detection, 72% having a detectable IgA response within the first 1.5 mo...... have therefore assessed the duration of secretory IgM and IgA antibody responses and whether assays for these antibodies can be used to improve the diagnosing of RSV-associated infections. During two RSV epidemics in Guinea-Bissau, 32 RSV antigen-positive children with LRI were followed with sequential...

  7. Respiratory syncytial virus infection in infants with acute leukemia: a retrospective survey of the Japanese Pediatric Leukemia/Lymphoma Study Group.

    Science.gov (United States)

    Hatanaka, Michiki; Miyamura, Takako; Koh, Katsuyoshi; Taga, Takashi; Tawa, Akio; Hasegawa, Daisuke; Kajihara, Ryosuke; Adachi, Souichi; Ishii, Eiichi; Tomizawa, Daisuke

    2015-12-01

    Respiratory syncytial virus (RSV) can cause life-threatening complications of lower respiratory tract infection (LRTI) in young children with malignancies, but reports remain limited. We performed a retrospective nationwide survey to clarify the current status of RSV disease among infants with hematological malignancies. Clinical course, treatment, and outcome of patients with hematological malignancies who suffered from RSV infections at the age of acute leukemia were identified as having experienced RSV disease. The primary diseases were acute myeloid leukemia (n = 8) and acute lymphoblastic leukemia (n = 4). RSV infection occurred pre- or during induction therapy (n = 8) and during consolidation therapy (n = 4). Eight patients developed LRTI, four of whom had severe pneumonia or acute respiratory distress syndrome; these four patients died despite receiving intensive care. In our survey, the prognosis of RSV disease in pediatric hematological malignancies was poor, and progression of LRTI in particular was associated with high mortality. In the absence of RSV-specific therapy, effective prevention and treatment strategies for severe RSV disease must be investigated.

  8. A cost-benefit analysis of the immunisation of children against respiratory syncytial virus (RSV) using the English Hospital Episode Statistics (HES) data set.

    Science.gov (United States)

    Thomas, Gareth

    2018-03-01

    Respiratory syncytial virus (RSV) is a common cause of respiratory infection that is highly prevalent in infants, particularly those with underlying medical conditions. Severe cases of RSV require hospitalisation as well as admission to intensive care and may even result in death. The objective of the study was to measure the net benefits that could arise from an immunisation programme of infants that may well eradicate RSV to a high degree and save the direct and indirect medical care costs from hospitalisation, morbidity and the gain from potential life-time earnings by reducing the probability of mortality. In this context, the majority of existing empirical investigations are based on data from clinical trials, and where relevant facts are not available, a series of strong assumptions is derived from the published literature, whereas in this study, for the first time, the hospital episode statistics database is used to calculate the cost-benefit ratios. The methodology of the analysis adopts a cost-benefit approach to assess the impact of the immunisation and whether it is beneficial to society. The underlying assumptions of the basic model are assessed by adopting a sensitivity analysis. The results show that a number of categories are cost-effective with the use of the passive drug, which means benefits by raising the life expectancy and quality as well as reducing the resource burden on society.

  9. Characterization of the CD8+ T cell responses directed against respiratory syncytial virus during primary and secondary infection in C57BL/6 mice

    International Nuclear Information System (INIS)

    Lukens, Michael V.; Claassen, Erwin A.W.; Graaff, Patricia M.A. de; Dijk, Mariska E.A. van; Hoogerhout, Peter; Toebes, Mireille; Schumacher, Ton N.; Most, Robbert G. van der; Kimpen, Jan L.L.; Bleek, Grada M. van

    2006-01-01

    The BALB/c mouse model for human respiratory syncytial virus infection has contributed significantly to our understanding of the relative role for CD4 + and CD8 + T cells to immune protection and pathogenic immune responses. To enable comparison of RSV-specific T cell responses in different mouse strains and allow dissection of immune mechanisms by using transgenic and knockout mice that are mostly available on a C57BL/6 background, we characterized the specificity, level and functional capabilities of CD8 + T cells during primary and secondary responses in lung parenchyma, airways and spleens of C57BL/6 mice. During the primary response, epitopes were recognized originating from the matrix, fusion, nucleo- and attachment proteins, whereas the secondary response focused predominantly on the matrix epitope. C57BL/6 mice are less permissive for hRSV infection than BALB/c mice, yet we found CD8 + T cell responses in the lungs and bronchoalveolar lavage, comparable to the responses described for BALB/c mice

  10. Analysis of JC virus DNA replication using a quantitative and high-throughput assay

    International Nuclear Information System (INIS)

    Shin, Jong; Phelan, Paul J.; Chhum, Panharith; Bashkenova, Nazym; Yim, Sung; Parker, Robert; Gagnon, David; Gjoerup, Ole; Archambault, Jacques; Bullock, Peter A.

    2014-01-01

    Progressive Multifocal Leukoencephalopathy (PML) is caused by lytic replication of JC virus (JCV) in specific cells of the central nervous system. Like other polyomaviruses, JCV encodes a large T-antigen helicase needed for replication of the viral DNA. Here, we report the development of a luciferase-based, quantitative and high-throughput assay of JCV DNA replication in C33A cells, which, unlike the glial cell lines Hs 683 and U87, accumulate high levels of nuclear T-ag needed for robust replication. Using this assay, we investigated the requirement for different domains of T-ag, and for specific sequences within and flanking the viral origin, in JCV DNA replication. Beyond providing validation of the assay, these studies revealed an important stimulatory role of the transcription factor NF1 in JCV DNA replication. Finally, we show that the assay can be used for inhibitor testing, highlighting its value for the identification of antiviral drugs targeting JCV DNA replication. - Highlights: • Development of a high-throughput screening assay for JCV DNA replication using C33A cells. • Evidence that T-ag fails to accumulate in the nuclei of established glioma cell lines. • Evidence that NF-1 directly promotes JCV DNA replication in C33A cells. • Proof-of-concept that the HTS assay can be used to identify pharmacological inhibitor of JCV DNA replication

  11. Analysis of JC virus DNA replication using a quantitative and high-throughput assay

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jong; Phelan, Paul J.; Chhum, Panharith; Bashkenova, Nazym; Yim, Sung; Parker, Robert [Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111 (United States); Gagnon, David [Institut de Recherches Cliniques de Montreal (IRCM), 110 Pine Avenue West, Montreal, Quebec, Canada H2W 1R7 (Canada); Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec (Canada); Gjoerup, Ole [Molecular Oncology Research Institute, Tufts Medical Center, Boston, MA 02111 (United States); Archambault, Jacques [Institut de Recherches Cliniques de Montreal (IRCM), 110 Pine Avenue West, Montreal, Quebec, Canada H2W 1R7 (Canada); Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Quebec (Canada); Bullock, Peter A., E-mail: Peter.Bullock@tufts.edu [Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111 (United States)

    2014-11-15

    Progressive Multifocal Leukoencephalopathy (PML) is caused by lytic replication of JC virus (JCV) in specific cells of the central nervous system. Like other polyomaviruses, JCV encodes a large T-antigen helicase needed for replication of the viral DNA. Here, we report the development of a luciferase-based, quantitative and high-throughput assay of JCV DNA replication in C33A cells, which, unlike the glial cell lines Hs 683 and U87, accumulate high levels of nuclear T-ag needed for robust replication. Using this assay, we investigated the requirement for different domains of T-ag, and for specific sequences within and flanking the viral origin, in JCV DNA replication. Beyond providing validation of the assay, these studies revealed an important stimulatory role of the transcription factor NF1 in JCV DNA replication. Finally, we show that the assay can be used for inhibitor testing, highlighting its value for the identification of antiviral drugs targeting JCV DNA replication. - Highlights: • Development of a high-throughput screening assay for JCV DNA replication using C33A cells. • Evidence that T-ag fails to accumulate in the nuclei of established glioma cell lines. • Evidence that NF-1 directly promotes JCV DNA replication in C33A cells. • Proof-of-concept that the HTS assay can be used to identify pharmacological inhibitor of JCV DNA replication.

  12. Favipiravir elicits antiviral mutagenesis during virus replication in vivo.

    Science.gov (United States)

    Arias, Armando; Thorne, Lucy; Goodfellow, Ian

    2014-10-21

    Lethal mutagenesis has emerged as a novel potential therapeutic approach to treat viral infections. Several studies have demonstrated that increases in the high mutation rates inherent to RNA viruses lead to viral extinction in cell culture, but evidence during infections in vivo is limited. In this study, we show that the broad-range antiviral nucleoside favipiravir reduces viral load in vivo by exerting antiviral mutagenesis in a mouse model for norovirus infection. Increased mutation frequencies were observed in samples from treated mice and were accompanied with lower or in some cases undetectable levels of infectious virus in faeces and tissues. Viral RNA isolated from treated animals showed reduced infectivity, a feature of populations approaching extinction during antiviral mutagenesis. These results suggest that favipiravir can induce norovirus mutagenesis in vivo, which in some cases leads to virus extinction, providing a proof-of-principle for the use of favipiravir derivatives or mutagenic nucleosides in the clinical treatment of noroviruses.

  13. Hsp90 inhibitors reduce influenza virus replication in cell culture

    International Nuclear Information System (INIS)

    Chase, Geoffrey; Deng, Tao; Fodor, Ervin; Leung, B.W.; Mayer, Daniel; Schwemmle, Martin; Brownlee, George

    2008-01-01

    The viral RNA polymerase complex of influenza A virus consists of three subunits PB1, PB2 and PA. Recently, the cellular chaperone Hsp90 was shown to play a role in nuclear import and assembly of the trimeric polymerase complex by binding to PB1 and PB2. Here we show that Hsp90 inhibitors, geldanamycin or its derivative 17-AAG, delay the growth of influenza virus in cell culture resulting in a 1-2 log reduction in viral titre early in infection. We suggest that this is caused by the reduced half-life of PB1 and PB2 and inhibition of nuclear import of PB1 and PA which lead to reduction in viral RNP assembly. Hsp90 inhibitors may represent a new class of antiviral compounds against influenza viruses

  14. MicroRNA regulation of human protease genes essential for influenza virus replication.

    Directory of Open Access Journals (Sweden)

    Victoria A Meliopoulos

    Full Text Available Influenza A virus causes seasonal epidemics and periodic pandemics threatening the health of millions of people each year. Vaccination is an effective strategy for reducing morbidity and mortality, and in the absence of drug resistance, the efficacy of chemoprophylaxis is comparable to that of vaccines. However, the rapid emergence of drug resistance has emphasized the need for new drug targets. Knowledge of the host cell components required for influenza replication has been an area targeted for disease intervention. In this study, the human protease genes required for influenza virus replication were determined and validated using RNA interference approaches. The genes validated as critical for influenza virus replication were ADAMTS7, CPE, DPP3, MST1, and PRSS12, and pathway analysis showed these genes were in global host cell pathways governing inflammation (NF-κB, cAMP/calcium signaling (CRE/CREB, and apoptosis. Analyses of host microRNAs predicted to govern expression of these genes showed that eight miRNAs regulated gene expression during virus replication. These findings identify unique host genes and microRNAs important for influenza replication providing potential new targets for disease intervention strategies.

  15. MicroRNA regulation of human protease genes essential for influenza virus replication.

    Science.gov (United States)

    Meliopoulos, Victoria A; Andersen, Lauren E; Brooks, Paula; Yan, Xiuzhen; Bakre, Abhijeet; Coleman, J Keegan; Tompkins, S Mark; Tripp, Ralph A

    2012-01-01

    Influenza A virus causes seasonal epidemics and periodic pandemics threatening the health of millions of people each year. Vaccination is an effective strategy for reducing morbidity and mortality, and in the absence of drug resistance, the efficacy of chemoprophylaxis is comparable to that of vaccines. However, the rapid emergence of drug resistance has emphasized the need for new drug targets. Knowledge of the host cell components required for influenza replication has been an area targeted for disease intervention. In this study, the human protease genes required for influenza virus replication were determined and validated using RNA interference approaches. The genes validated as critical for influenza virus replication were ADAMTS7, CPE, DPP3, MST1, and PRSS12, and pathway analysis showed these genes were in global host cell pathways governing inflammation (NF-κB), cAMP/calcium signaling (CRE/CREB), and apoptosis. Analyses of host microRNAs predicted to govern expression of these genes showed that eight miRNAs regulated gene expression during virus replication. These findings identify unique host genes and microRNAs important for influenza replication providing potential new targets for disease intervention strategies.

  16. Definition of herpes simplex virus type 1 helper activities for adeno-associated virus early replication events.

    Directory of Open Access Journals (Sweden)

    Nathalie Alazard-Dany

    2009-03-01

    Full Text Available The human parvovirus Adeno-Associated Virus (AAV type 2 can only replicate in cells co-infected with a helper virus, such as Adenovirus or Herpes Simplex Virus type 1 (HSV-1; whereas, in the absence of a helper virus, it establishes a latent infection. Previous studies demonstrated that the ternary HSV-1 helicase/primase (HP complex (UL5/8/52 and the single-stranded DNA-Binding Protein (ICP8 were sufficient to induce AAV-2 replication in transfected cells. We independently showed that, in the context of a latent AAV-2 infection, the HSV-1 ICP0 protein was able to activate rep gene expression. The present study was conducted to integrate these observations and to further explore the requirement of other HSV-1 proteins during early AAV replication steps, i.e. rep gene expression and AAV DNA replication. Using a cellular model that mimics AAV latency and composite constructs coding for various sets of HSV-1 genes, we first confirmed the role of ICP0 for rep gene expression and demonstrated a synergistic effect of ICP4 and, to a lesser extent, ICP22. Conversely, ICP27 displayed an inhibitory effect. Second, our analyses showed that the effect of ICP0, ICP4, and ICP22 on rep gene expression was essential for the onset of AAV DNA replication in conjunction with the HP complex and ICP8. Third, and most importantly, we demonstrated that the HSV-1 DNA polymerase complex (UL30/UL42 was critical to enhance AAV DNA replication to a significant level in transfected cells and that its catalytic activity was involved in this process. Altogether, this work represents the first comprehensive study recapitulating the series of early events taking place during HSV-1-induced AAV replication.

  17. Evidence of Ebola Virus Replication and High Concentration in Semen of a Patient During Recovery.

    Science.gov (United States)

    Barnes, Kayla G; Kindrachuk, Jason; Lin, Aaron E; Wohl, Shirlee; Qu, James; Tostenson, Samantha D; Dorman, William R; Busby, Michele; Siddle, Katherine J; Luo, Cynthia Y; Matranga, Christian B; Davey, Richard T; Sabeti, Pardis C; Chertow, Daniel S

    2017-10-15

    In one patient over time, we found that concentration of Ebola virus RNA in semen during recovery is remarkably higher than blood at peak illness. Virus in semen is replication-competent with no change in viral genome over time. Presence of sense RNA suggests replication in cells present in semen. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  18. Transgene stability for three replication competent murine leukemia virus vectors

    DEFF Research Database (Denmark)

    Duch, M.; Carrasco, M.L.; Jespersen, T.

    2004-01-01

    cassette consisting of an internal ribosome entry site followed by the enhanced green fluorescent protein coding sequence inserted in different configurations into murine leukemia virus genomes. In two of the constructs, the insert was located in the upstream part of the U3 region while in the third...

  19. Polyamine biosynthesis and the replication of turnip yellow mosaic virus

    International Nuclear Information System (INIS)

    Balint, R.F.

    1984-01-01

    Turnip yellow mosaic virus (TYMV) contains large amounts of nonexchangeable spermidine and induces an accumulation of spermidine in infected Chinese cabbage. By seven days after inoculation, a majority of protoplasts isolated from newly-emerging leaves stain with fluorescent antibody to the virus. These protoplasts contain 1-2 x 10 6 virions per cell and continue to produce virus in culture for at least 48 hours. [ 14 C]-Spermidine (10 μM) was taken up by these cells in amounts comparable to the original endogenous pool within 24 hours. However, the spermidine content of the cell was only marginally affected, implying considerable regulation of the endogenous pool(s). Putrescine and spermine were major products of the metabolism of exogenous spermidine. Radioactivity from exogenous [ 14 C]-spermidine was also readily incorporated into the nucleic acid-containing component of the virus, where it appeared as both spermidine and spermine. Thus, newly-formed virions contained predominantly newly-synthesized spermidine and spermine. However, inhibition of spermidine synthesis by dicyclohexylamine (DCHA) led to incorporation of pre-existing spermidine and increased amounts of spermine into newly-formed virions. The latter results were tested and confirmed in a second cellular system, consisting of health protoplasts infected with TYMC in vitro

  20. Activation of cytokines and NF-kappa B in corneal epithelial cells infected by respiratory syncytial virus: potential relevance in ocular inflammation and respiratory infection

    Directory of Open Access Journals (Sweden)

    Oakes John E

    2004-07-01

    Full Text Available Abstract Background Respiratory syncytial virus (RSV is a major cause of lower respiratory tract infection, claiming millions of lives annually. The virus infects various cells of the respiratory tract as well as resident inflammatory cells such as macrophages. Infection activates a variety of cellular factors such as cytokines and the pro-inflammatory transcription factor, NF-kappa B, all of which are important players in the respiratory disease. However, the exact natural route of RSV infection and its etiology remain relatively unknown. In this paper, we test the hypothesis that human corneal epithelial cells, which constitute the outermost layer of the cornea, can be infected with RSV, and that the infection leads to the activation of proinflammatory macromolecules. Results Corneal swabs obtained from pediatric patients with acute respiratory disease were found to contain RSV at a high frequency (43 positive out of 72 samples, i.e., 60%. Primary corneal epithelial cells in tissue culture supported robust infection and productive growth of RSV. Infection resulted in the activation of TNF-α, IL-6 and sixteen chemokines as well as NF-κB. Three proinflammatory CXC chemokines (MIG, I-TAC, IP-10 underwent the greatest activation. Conclusions The ocular epithelium is readily infected by RSV. The pro-inflammatory cytokines are likely to play critical roles in the etiology of inflammation and conjunctivitis commonly seen in pediatric patients with respiratory infections. RSV-eye interactions have important implications in RSV transmission, immunopathology of RSV disease, and in the management of conjunctivitis.

  1. Seasonality of Influenza and Respiratory Syncytial Viruses and the Effect of Climate Factors in Subtropical-Tropical Asia Using Influenza-Like Illness Surveillance Data, 2010 -2012.

    Science.gov (United States)

    Kamigaki, Taro; Chaw, Liling; Tan, Alvin G; Tamaki, Raita; Alday, Portia P; Javier, Jenaline B; Olveda, Remigio M; Oshitani, Hitoshi; Tallo, Veronica L

    2016-01-01

    The seasonality of influenza and respiratory syncytial virus (RSV) is well known, and many analyses have been conducted in temperate countries; however, this is still not well understood in tropical countries. Previous studies suggest that climate factors are involved in the seasonality of these viruses. However, the extent of the effect of each climate variable is yet to be defined. We investigated the pattern of seasonality and the effect of climate variables on influenza and RSV at three sites of different latitudes: the Eastern Visayas region and Baguio City in the Philippines, and Okinawa Prefecture in Japan. Wavelet analysis and the dynamic linear regression model were applied. Climate variables used in the analysis included mean temperature, relative and specific humidity, precipitation, and number of rainy days. The Akaike Information Criterion estimated in each model was used to test the improvement of fit in comparison with the baseline model. At all three study sites, annual seasonal peaks were observed in influenza A and RSV; peaks were unclear for influenza B. Ranges of climate variables at the two Philippine sites were narrower and mean variables were significantly different among the three sites. Whereas all climate variables except the number of rainy days improved model fit to the local trend model, their contributions were modest. Mean temperature and specific humidity were positively associated with influenza and RSV at the Philippine sites and negatively associated with influenza A in Okinawa. Precipitation also improved model fit for influenza and RSV at both Philippine sites, except for the influenza A model in the Eastern Visayas. Annual seasonal peaks were observed for influenza A and RSV but were less clear for influenza B at all three study sites. Including additional data from subsequent more years would help to ascertain these findings. Annual amplitude and variation in climate variables are more important than their absolute values for

  2. Delta inulin-derived adjuvants that elicit Th1 phenotype following vaccination reduces respiratory syncytial virus lung titers without a reduction in lung immunopathology.

    Science.gov (United States)

    Wong, Terianne M; Petrovsky, Nikolai; Bissel, Stephanie J; Wiley, Clayton A; Ross, Ted M

    2016-08-02

    Respiratory syncytial virus (RSV) is a significant cause of lower respiratory tract infections resulting in bronchiolitis and even mortality in the elderly and young children/infants. Despite the impact of this virus on human health, no licensed vaccine exists. Unlike many other viral infections, RSV infection or vaccination does not induce durable protective antibodies in humans. In order to elicit high titer, neutralizing antibodies against RSV, we investigated the use of the adjuvant Advax™, a novel polysaccharide adjuvant based on delta inulin microparticles, to enhance antibody titers following vaccination. BALB/c mice were vaccinated intramuscularly with live RSV as a vaccine antigen in combination with one of two formulations of Advax™. Advax-1 was comprised of the standard delta inulin adjuvant and Advax-2 was formulated delta inulin plus CpG oligodendronucleotides (ODNs). An additional group of mice were either mock vaccinated, immunized with vaccine only, or administered vaccine plus Imject Alum. Following 3 vaccinations, mice had neutralizing antibody titers that correlated with reduction in viral titers in the lungs. Advax-1 significantly enhanced serum RSV-specific IgG1 levels at week 6 indicative of a Th2 response, similar to titers in mice administered vaccine plus Imject Alum. In contrast, mice vaccinated with vaccine plus Advax-2 had predominately IgG2a titers indicative of a Th1 response that was maintained during the entire study. Interestingly, regardless of which Advax TM adjuvant was used, the neutralizing titers were similar between groups, but the viral lung titers were significantly lower (∼10E+3pfu/g) in mice administered vaccine with either Advax TM adjuvant compared to mice administered adjuvants only. The lung pathology in vaccinated mice with Advax TM was similar to Imject Alum. Overall, RSV vaccine formulated with Advax TM had high neutralizing antibody titers with low lung viral titers, but exacerbated lung pathology compared

  3. Seasonality of Influenza and Respiratory Syncytial Viruses and the Effect of Climate Factors in Subtropical-Tropical Asia Using Influenza-Like Illness Surveillance Data, 2010 -2012.

    Directory of Open Access Journals (Sweden)

    Taro Kamigaki

    Full Text Available The seasonality of influenza and respiratory syncytial virus (RSV is well known, and many analyses have been conducted in temperate countries; however, this is still not well understood in tropical countries. Previous studies suggest that climate factors are involved in the seasonality of these viruses. However, the extent of the effect of each climate variable is yet to be defined.We investigated the pattern of seasonality and the effect of climate variables on influenza and RSV at three sites of different latitudes: the Eastern Visayas region and Baguio City in the Philippines, and Okinawa Prefecture in Japan. Wavelet analysis and the dynamic linear regression model were applied. Climate variables used in the analysis included mean temperature, relative and specific humidity, precipitation, and number of rainy days. The Akaike Information Criterion estimated in each model was used to test the improvement of fit in comparison with the baseline model.At all three study sites, annual seasonal peaks were observed in influenza A and RSV; peaks were unclear for influenza B. Ranges of climate variables at the two Philippine sites were narrower and mean variables were significantly different among the three sites. Whereas all climate variables except the number of rainy days improved model fit to the local trend model, their contributions were modest. Mean temperature and specific humidity were positively associated with influenza and RSV at the Philippine sites and negatively associated with influenza A in Okinawa. Precipitation also improved model fit for influenza and RSV at both Philippine sites, except for the influenza A model in the Eastern Visayas.Annual seasonal peaks were observed for influenza A and RSV but were less clear for influenza B at all three study sites. Including additional data from subsequent more years would help to ascertain these findings. Annual amplitude and variation in climate variables are more important than their

  4. Structure and functional analysis of the RNA- and viral phosphoprotein-binding domain of respiratory syncytial virus M2-1 protein.

    Directory of Open Access Journals (Sweden)

    Marie-Lise Blondot

    Full Text Available Respiratory syncytial virus (RSV protein M2-1 functions as an essential transcriptional cofactor of the viral RNA-dependent RNA polymerase (RdRp complex by increasing polymerase processivity. M2-1 is a modular RNA binding protein that also interacts with the viral phosphoprotein P, another component of the RdRp complex. These binding properties are related to the core region of M2-1 encompassing residues S58 to K177. Here we report the NMR structure of the RSV M2-1(58-177 core domain, which is structurally homologous to the C-terminal domain of Ebola virus VP30, a transcription co-factor sharing functional similarity with M2-1. The partial overlap of RNA and P interaction surfaces on M2-1(58-177, as determined by NMR, rationalizes the previously observed competitive behavior of RNA versus P. Using site-directed mutagenesis, we identified eight residues located on these surfaces that are critical for an efficient transcription activity of the RdRp complex. Single mutations of these residues disrupted specifically either P or RNA binding to M2-1 in vitro. M2-1 recruitment to cytoplasmic inclusion bodies, which are regarded as sites of viral RNA synthesis, was impaired by mutations affecting only binding to P, but not to RNA, suggesting that M2-1 is associated to the holonucleocapsid by interacting with P. These results reveal that RNA and P binding to M2-1 can be uncoupled and that both are critical for the transcriptional antitermination function of M2-1.

  5. Varicella-zoster virus (VZV) origin of DNA replication oriS influences origin-dependent DNA replication and flanking gene transcription.

    Science.gov (United States)

    Khalil, Mohamed I; Sommer, Marvin H; Hay, John; Ruyechan, William T; Arvin, Ann M

    2015-07-01

    The VZV genome has two origins of DNA replication (oriS), each of which consists of an AT-rich sequence and three origin binding protein (OBP) sites called Box A, C and B. In these experiments, the mutation in the core sequence CGC of the Box A and C not only inhibited DNA replication but also inhibited both ORF62 and ORF63 expression in reporter gene assays. In contrast the Box B mutation did not influence DNA replication or flanking gene transcription. These results suggest that efficient DNA replication enhances ORF62 and ORF63 transcription. Recombinant viruses carrying these mutations in both sites and one with a deletion of the whole oriS were constructed. Surprisingly, the recombinant virus lacking both copies of oriS retained the capacity to replicate in melanoma and HELF cells suggesting that VZV has another origin of DNA replication. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Human cytomegalovirus renders cells non-permissive for replication of herpes simplex viruses

    International Nuclear Information System (INIS)

    Cockley, K.D.

    1988-01-01

    The herpes simplex virus (HSV) genome during production infection in vitro may be subject to negative regulation which results in modification of the cascade of expression of herpes virus macromolecular synthesis leading to establishment of HSV latency. In the present study, human embryonic lung (HEL) cells infected with human cytomegalovirus (HCMV) restricted the replication of HSV type-1 (HSV-1). A delay in HSV replication of 15 hr as well as a consistent, almost 1000-fold inhibition of HSV replication in HCMV-infected cell cultures harvested 24 to 72 hr after superinfection were observed compared with controls infected with HSV alone. HSV type-2 (HSV-2) replication was similarly inhibited in HCMV-infected HEL cells. Prior ultraviolet-irradiation (UV) of HCMV removed the block to HSV replication, demonstrating the requirement for an active HCMV genome. HCMV deoxyribonucleic acid (DNA) negative temperature-sensitive (ts) mutants inhibited HSV replications as efficiently as wild-type (wt) HCMV at the non-permissive temperature. Evidence for penetration and replication of superinfecting HSV into HCMV-infected cells was provided by blot hybridization of HSV DNA synthesized in HSV-superinfected cell cultures and by cesium chloride density gradient analysis of [ 3 H]-labeled HSV-1-superinfected cells

  7. Zika virus replication in the mosquito Culex quinquefasciatus in Brazil.

    Science.gov (United States)

    Guedes, Duschinka Rd; Paiva, Marcelo Hs; Donato, Mariana Ma; Barbosa, Priscilla P; Krokovsky, Larissa; Rocha, Sura W Dos S; Saraiva, Karina LA; Crespo, Mônica M; Rezende, Tatiana Mt; Wallau, Gabriel L; Barbosa, Rosângela Mr; Oliveira, Cláudia Mf; Melo-Santos, Maria Av; Pena, Lindomar; Cordeiro, Marli T; Franca, Rafael F de O; Oliveira, André Ls de; Peixoto, Christina A; Leal, Walter S; Ayres, Constância Fj

    2017-08-09

    Zika virus (ZIKV) is a flavivirus that has recently been associated with an increased incidence of neonatal microcephaly and other neurological disorders. The virus is primarily transmitted by mosquito bite, although other routes of infection have been implicated in some cases. The Aedes aegypti mosquito is considered to be the main vector to humans worldwide; however, there is evidence that other mosquito species, including Culex quinquefasciatus, transmit the virus. To test the potential of Cx. quinquefasciatus to transmit ZIKV, we experimentally compared the vector competence of laboratory-reared Ae. aegypti and Cx. quinquefasciatus. Interestingly, we were able to detect the presence of ZIKV in the midgut, salivary glands and saliva of artificially fed Cx. quinquefasciatus. In addition, we collected ZIKV-infected Cx. quinquefasciatus from urban areas with high microcephaly incidence in Recife, Brazil. Corroborating our experimental data from artificially fed mosquitoes, ZIKV was isolated from field-caught Cx. quinquefasciatus, and its genome was partially sequenced. Collectively, these findings indicate that there may be a wider range of ZIKV vectors than anticipated.

  8. Oncolytic targeting of androgen-sensitive prostate tumor by the respiratory syncytial virus (RSV): consequences of deficient interferon-dependent antiviral defense

    International Nuclear Information System (INIS)

    Echchgadda, Ibtissam; Chang, Te-Hung; Sabbah, Ahmed; Bakri, Imad; Ikeno, Yuji; Hubbard, Gene B; Chatterjee, Bandana; Bose, Santanu

    2011-01-01

    Oncolytic virotherapy for cancer treatment utilizes viruses for selective infection and death of cancer cells without any adverse effect on normal cells. We previously reported that the human respiratory syncytial virus (RSV) is a novel oncolytic virus against androgen-independent PC-3 human prostate cancer cells. The present study extends the result to androgen-dependent prostate cancer, and explores the underlying mechanism that triggers RSV-induced oncolysis of prostate cancer cells. The oncolytic effect of RSV on androgen-sensitive LNCaP human prostate cancer cells and on androgen-independent RM1 murine prostate cancer cells was studied in vitro in culture and in vivo in a xenograft or allograft tumor model. In vitro, cell viability, infectivity and apoptosis were monitored by MTT assay, viral plaque assay and annexin V staining, respectively. In vivo studies involved virus administration to prostate tumors grown in immune compromised nude mice and in syngeneic immune competent C57BL/6J mice. Anti-tumorogenic oncolytic activity was monitored by measuring tumor volume, imaging bioluminescent tumors in live animals and performing histopathological analysis and TUNEL assay with tumors We show that RSV imposes a potent oncolytic effect on LNCaP prostate cancer cells. RSV infectivity was markedly higher in LNCaP cells compared to the non-tumorigenic RWPE-1 human prostate cells. The enhanced viral burden led to LNCaP cell apoptosis and growth inhibition of LNCaP xenograft tumors in nude mice. A functional host immune response did not interfere with RSV-induced oncolysis, since growth of xenograft tumors in syngeneic C57BL/6J mice from murine RM1 cells was inhibited upon RSV administration. LNCaP cells failed to activate the type-I interferon (IFNα/β)-induced transcription factor STAT-1, which is required for antiviral gene expression, although these cells could produce IFN in response to RSV infection. The essential role of IFN in restricting infection was further

  9. The low-pH stability discovered in neuraminidase of 1918 pandemic influenza A virus enhances virus replication.

    Directory of Open Access Journals (Sweden)

    Tadanobu Takahashi

    Full Text Available The "Spanish" pandemic influenza A virus, which killed more than 20 million worldwide in 1918-19, is one of the serious pathogens in recorded history. Characterization of the 1918 pandemic virus reconstructed by reverse genetics showed that PB1, hemagglutinin (HA, and neuraminidase (NA genes contributed to the viral replication and virulence of the 1918 pandemic influenza virus. However, the function of the NA gene has remained unknown. Here we show that the avian-like low-pH stability of sialidase activity discovered in the 1918 pandemic virus NA contributes to the viral replication efficiency. We found that deletion of Thr at position 435 or deletion of Gly at position 455 in the 1918 pandemic virus NA was related to the low-pH stability of the sialidase activity in the 1918 pandemic virus NA by comparison with the sequences of other human N1 NAs and sialidase activity of chimeric constructs. Both amino acids were located in or near the amino acid resides that were important for stabilization of the native tetramer structure in a low-pH condition like the N2 NAs of pandemic viruses that emerged in 1957 and 1968. Two reverse-genetic viruses were generated from a genetic background of A/WSN/33 (H1N1 that included low-pH-unstable N1 NA from A/USSR/92/77 (H1N1 and its counterpart N1 NA in which sialidase activity was converted to a low-pH-stable property by a deletion and substitutions of two amino acid residues at position 435 and 455 related to the low-pH stability of the sialidase activity in 1918 NA. The mutant virus that included "Spanish Flu"-like low-pH-stable NA showed remarkable replication in comparison with the mutant virus that included low-pH-unstable N1 NA. Our results suggest that the avian-like low-pH stability of sialidase activity in the 1918 pandemic virus NA contributes to the viral replication efficiency.

  10. NB protein does not affect influenza B virus replication in vitro and is not required for replication in or transmission between ferrets

    Science.gov (United States)

    Elderfield, Ruth A.; Koutsakos, Marios; Frise, Rebecca; Bradley, Konrad; Ashcroft, Jonathan; Miah, Shanhjahan; Lackenby, Angie

    2016-01-01

    The influenza B virus encodes a unique protein, NB, a membrane protein whose function in the replication cycle is not, as yet, understood. We engineered a recombinant influenza B virus lacking NB expression, with no concomitant difference in expression or activity of viral neuraminidase (NA) protein, an important caveat since NA is encoded on the same segment and initiated from a start codon just 4 nt downstream of NB. Replication of the virus lacking NB was not different to wild-type virus with full-length NB in clonal immortalized or complex primary cell cultures. In the mouse model, virus lacking NB induced slightly lower IFN-α levels in infected lungs, but this did not affect virus titres or weight loss. In ferrets infected with a mixture of viruses that did or did not express NB, there was no fitness advantage for the virus that retained NB. Moreover, virus lacking NB protein was transmitted following respiratory droplet exposure of sentinel animals. These data suggest no role for NB in supporting replication or transmission in vivo in this animal model. The role of NB and the nature of selection to retain it in all natural influenza B viruses remain unclear. PMID:26703440

  11. Complex Virus-Host Interactions Involved in the Regulation of Classical Swine Fever Virus Replication: A Minireview.

    Science.gov (United States)

    Li, Su; Wang, Jinghan; Yang, Qian; Naveed Anwar, Muhammad; Yu, Shaoxiong; Qiu, Hua-Ji

    2017-07-05

    Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is one of the most devastating epizootic diseases of pigs in many countries. Viruses are small intracellular parasites and thus rely on the cellular factors for replication. Fundamental aspects of CSFV-host interactions have been well described, such as factors contributing to viral attachment, modulation of genomic replication and translation, antagonism of innate immunity, and inhibition of cell apoptosis. However, those host factors that participate in the viral entry, assembly, and release largely remain to be elucidated. In this review, we summarize recent progress in the virus-host interactions involved in the life cycle of CSFV and analyze the potential mechanisms of viral entry, assembly, and release. We conclude with future perspectives and highlight areas that require further understanding.

  12. Active RNA replication of hepatitis C virus downregulates CD81 expression.

    Science.gov (United States)

    Ke, Po-Yuan; Chen, Steve S-L

    2013-01-01

    So far how hepatitis C virus (HCV) replication modulates subsequent virus growth and propagation still remains largely unknown. Here we determine the impact of HCV replication status on the consequential virus growth by comparing normal and high levels of HCV RNA expression. We first engineered a full-length, HCV genotype 2a JFH1 genome containing a blasticidin-resistant cassette inserted at amino acid residue of 420 in nonstructural (NS) protein 5A, which allowed selection of human hepatoma Huh7 cells stably-expressing HCV. Short-term establishment of HCV stable cells attained a highly-replicating status, judged by higher expressions of viral RNA and protein as well as higher titer of viral infectivity as opposed to cells harboring the same genome without selection. Interestingly, maintenance of highly-replicating HCV stable cells led to decreased susceptibility to HCV pseudotyped particle (HCVpp) infection and downregulated cell surface level of CD81, a critical HCV entry (co)receptor. The decreased CD81 cell surface expression occurred through reduced total expression and cytoplasmic retention of CD81 within an endoplasmic reticulum -associated compartment. Moreover, productive viral RNA replication in cells harboring a JFH1 subgenomic replicon containing a similar blasticidin resistance gene cassette in NS5A and in cells robustly replicating full-length infectious genome also reduced permissiveness to HCVpp infection through decreasing the surface expression of CD81. The downregulation of CD81 surface level in HCV RNA highly-replicating cells thus interfered with reinfection and led to attenuated viral amplification. These findings together indicate that the HCV RNA replication status plays a crucial determinant in HCV growth by modulating the expression and intracellular localization of CD81.

  13. Active RNA replication of hepatitis C virus downregulates CD81 expression.

    Directory of Open Access Journals (Sweden)

    Po-Yuan Ke

    Full Text Available So far how hepatitis C virus (HCV replication modulates subsequent virus growth and propagation still remains largely unknown. Here we determine the impact of HCV replication status on the consequential virus growth by comparing normal and high levels of HCV RNA expression. We first engineered a full-length, HCV genotype 2a JFH1 genome containing a blasticidin-resistant cassette inserted at amino acid residue of 420 in nonstructural (NS protein 5A, which allowed selection of human hepatoma Huh7 cells stably-expressing HCV. Short-term establishment of HCV stable cells attained a highly-replicating status, judged by higher expressions of viral RNA and protein as well as higher titer of viral infectivity as opposed to cells harboring the same genome without selection. Interestingly, maintenance of highly-replicating HCV stable cells led to decreased susceptibility to HCV pseudotyped particle (HCVpp infection and downregulated cell surface level of CD81, a critical HCV entry (coreceptor. The decreased CD81 cell surface expression occurred through reduced total expression and cytoplasmic retention of CD81 within an endoplasmic reticulum -associated compartment. Moreover, productive viral RNA replication in cells harboring a JFH1 subgenomic replicon containing a similar blasticidin resistance gene cassette in NS5A and in cells robustly replicating full-length infectious genome also reduced permissiveness to HCVpp infection through decreasing the surface expression of CD81. The downregulation of CD81 surface level in HCV RNA highly-replicating cells thus interfered with reinfection and led to attenuated viral amplification. These findings together indicate that the HCV RNA replication status plays a crucial determinant in HCV growth by modulating the expression and intracellular localization of CD81.

  14. Dendritic cells in dengue virus infection: Targets of virus replication and mediators of immunity

    Directory of Open Access Journals (Sweden)

    Michael A. Schmid

    2014-12-01

    Full Text Available Dendritic cells (DCs are sentinels of the immune system and detect pathogens at sites of entry, such as the skin. In addition to the ability of DCs to control infections directly via their innate immune functions, DCs help to prime adaptive B and T cell responses via antigen presentation in lymphoid tissues. Infected Aedes aegypti or Ae. albopictus mosquitoes transmit the four dengue virus (DENV serotypes to humans while probing for small blood vessels in the skin. DENV causes the most prevalent arthropod-borne viral disease in humans, yet no vaccine or specific therapeutic is currently approved. Although primary DENV infection confers life-long protective immunity against re-infection with the same DENV serotype, secondary infection with a different DENV serotype can lead to increased disease severity via cross-reactive T cells or enhancing antibodies. This review summarizes recent findings in humans and animal models about DENV infection of DCs, monocytes and macrophages. We discuss the dual role of DCs as both targets of DENV replication and mediators of innate and adaptive immunity, and summarize immune evasion strategies whereby DENV impairs the function of infected DCs. We suggest that DCs play a key role in priming DENV-specific neutralizing or potentially harmful memory B and T cell responses, and that future DC-directed therapies may help induce protective memory responses and reduce dengue pathogenesis.

  15. Targeting Virus-host Interactions of HIV Replication.

    Science.gov (United States)

    Weydert, Caroline; De Rijck, Jan; Christ, Frauke; Debyser, Zeger

    2016-01-01

    Cellular proteins that are hijacked by HIV in order to complete its replication cycle, form attractive new targets for antiretroviral therapy. In particular, the protein-protein interactions between these cellular proteins (cofactors) and viral proteins are of great interest to develop new therapies. Research efforts have led to the validation of different cofactors and some successes in therapeutic applications. Maraviroc, the first cofactor inhibitor approved for human medicinal use, provided a proof of concept. Furthermore, compounds developed as Integrase-LEDGF/p75 interaction inhibitors (LEDGINs) have advanced to early clinical trials. Other compounds targeting cofactors and cofactor-viral protein interactions are currently under development. Likewise, interactions between cellular restriction factors and their counteracting HIV protein might serve as interesting targets in order to impair HIV replication. In this respect, compounds targeting the Vif-APOBEC3G interaction have been described. In this review, we focus on compounds targeting the Integrase- LEDGF/p75 interaction, the Tat-P-TEFb interaction and the Vif-APOBEC3G interaction. Additionally we give an overview of currently discovered compounds presumably targeting cellular cofactor-HIV protein interactions.

  16. Effects of morphine on replication of herpes simplex virus type 1 and 2

    African Journals Online (AJOL)

    USER

    2009-05-17

    May 17, 2009 ... virus genome has a double strand DNA which codes over. 70 gene products. HSV infection is the most ... essential for viral replication, unlike viral DNA poly- merase. It seems that an alternative method of ... tral red was used and plaques were counted after 12 h. Determination of morphine cytotoxicity.

  17. Replication of an incomplete alfalfa mosaic virus genome in plants transformed with viral replicase genes

    NARCIS (Netherlands)

    Taschner, P. E.; van der Kuyl, A. C.; Neeleman, L.; Bol, J. F.

    1991-01-01

    RNAs 1 and 2 of alfalfa mosaic virus (AIMV) encode proteins P1 and P2, respectively, both of which have a putative role in viral RNA replication. Tobacco plants were transformed with DNA copies of RNA1 (P1-plants), RNA2 (P2-plants) or a combination of these two cDNAs (P12-plants). All transgenic

  18. Ocular Tropism of Respiratory Viruses

    Science.gov (United States)

    Rota, Paul A.; Tumpey, Terrence M.

    2013-01-01

    SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

  19. Herpes simplex virus replication compartments can form by coalescence of smaller compartments

    International Nuclear Information System (INIS)

    Taylor, Travis J; McNamee, Elizabeth E.; Day, Cheryl; Knipe, David M.

    2003-01-01

    Herpes simplex virus (HSV) uses intranuclear compartmentalization to concentrate the viral and cellular factors required for the progression of the viral life cycle. Processes as varied as viral DNA replication, late gene expression, and capsid assembly take place within discrete structures within the nucleus called replication compartments. Replication compartments are hypothesized to mature from a few distinct structures, called prereplicative sites, that form adjacent to cellular nuclear matrix-associated ND10 sites. During productive infection, the HSV single-stranded DNA-binding protein ICP8 localizes to replication compartments. To further the understanding of replication compartment maturation, we have constructed and characterized a recombinant HSV-1 strain that expresses an ICP8 molecule with green fluorescent protein (GFP) fused to its C terminus. In transfected Vero cells that were infected with HSV, the ICP8-GFP protein localized to prereplicative sites in the presence of the viral DNA synthesis inhibitor phosphonoacetic acid (PAA) or to replication compartments in the absence of PAA. A recombinant HSV-1 strain expressing the ICP8-GFP virus replicated in Vero cells, but the yield was increased by 150-fold in an ICP8-complementing cell line. Using the ICP8-GFP protein as a marker for replication compartments, we show here that these structures start as punctate structures early in infection and grow into large, globular structures that eventually fill the nucleus. Large replication compartments were formed by small structures that either moved through the nucleus to merge with adjacent compartments or remained relatively stationary within the nucleus and grew by accretion and fused with neighboring structures

  20. Essential role of cyclophilin A for hepatitis C virus replication and virus production and possible link to polyprotein cleavage kinetics.

    Directory of Open Access Journals (Sweden)

    Artur Kaul

    2009-08-01

    Full Text Available Viruses are obligate intracellular parasites and therefore their replication completely depends on host cell factors. In case of the hepatitis C virus (HCV, a positive-strand RNA virus that in the majority of infections establishes persistence, cyclophilins are considered to play an important role in RNA replication. Subsequent to the observation that cyclosporines, known to sequester cyclophilins by direct binding, profoundly block HCV replication in cultured human hepatoma cells, conflicting results were obtained as to the particular cyclophilin (Cyp required for viral RNA replication and the underlying possible mode of action. By using a set of cell lines with stable knock-down of CypA or CypB, we demonstrate in the present work that replication of subgenomic HCV replicons of different genotypes is reduced by CypA depletion up to 1,000-fold whereas knock-down of CypB had no effect. Inhibition of replication was rescued by over-expression of wild type CypA, but not by a mutant lacking isomerase activity. Replication of JFH1-derived full length genomes was even more sensitive to CypA depletion as compared to subgenomic replicons and virus production was completely blocked. These results argue that CypA may target an additional viral factor outside of the minimal replicase contributing to RNA amplification and assembly, presumably nonstructural protein 2. By selecting for resistance against the cyclosporine analogue DEBIO-025 that targets CypA in a dose-dependent manner, we identified two mutations (V2440A and V2440L close to the cleavage site between nonstructural protein 5A and the RNA-dependent RNA polymerase in nonstructural protein 5B that slow down cleavage kinetics at this site and reduce CypA dependence of viral replication. Further amino acid substitutions at the same cleavage site accelerating processing increase CypA dependence. Our results thus identify an unexpected correlation between HCV polyprotein processing and CypA dependence

  1. Essential role of cyclophilin A for hepatitis C virus replication and virus production and possible link to polyprotein cleavage kinetics.

    Science.gov (United States)

    Kaul, Artur; Stauffer, Sarah; Berger, Carola; Pertel, Thomas; Schmitt, Jennifer; Kallis, Stephanie; Zayas, Margarita; Lopez, Margarita Zayas; Lohmann, Volker; Luban, Jeremy; Bartenschlager, Ralf

    2009-08-01

    Viruses are obligate intracellular parasites and therefore their replication completely depends on host cell factors. In case of the hepatitis C virus (HCV), a positive-strand RNA virus that in the majority of infections establishes persistence, cyclophilins are considered to play an important role in RNA replication. Subsequent to the observation that cyclosporines, known to sequester cyclophilins by direct binding, profoundly block HCV replication in cultured human hepatoma cells, conflicting results were obtained as to the particular cyclophilin (Cyp) required for viral RNA replication and the underlying possible mode of action. By using a set of cell lines with stable knock-down of CypA or CypB, we demonstrate in the present work that replication of subgenomic HCV replicons of different genotypes is reduced by CypA depletion up to 1,000-fold whereas knock-down of CypB had no effect. Inhibition of replication was rescued by over-expression of wild type CypA, but not by a mutant lacking isomerase activity. Replication of JFH1-derived full length genomes was even more sensitive to CypA depletion as compared to subgenomic replicons and virus production was completely blocked. These results argue that CypA may target an additional viral factor outside of the minimal replicase contributing to RNA amplification and assembly, presumably nonstructural protein 2. By selecting for resistance against the cyclosporine analogue DEBIO-025 that targets CypA in a dose-dependent manner, we identified two mutations (V2440A and V2440L) close to the cleavage site between nonstructural protein 5A and the RNA-dependent RNA polymerase in nonstructural protein 5B that slow down cleavage kinetics at this site and reduce CypA dependence of viral replication. Further amino acid substitutions at the same cleavage site accelerating processing increase CypA dependence. Our results thus identify an unexpected correlation between HCV polyprotein processing and CypA dependence of HCV

  2. Replication and Transmission of the Novel Bovine Influenza D Virus in a Guinea Pig Model.

    Science.gov (United States)

    Sreenivasan, Chithra; Thomas, Milton; Sheng, Zizhang; Hause, Ben M; Collin, Emily A; Knudsen, David E B; Pillatzki, Angela; Nelson, Eric; Wang, Dan; Kaushik, Radhey S; Li, Feng

    2015-12-01

    Influenza D virus (FLUDV) is a novel influenza virus that infects cattle and swine. The goal of this study was to investigate the replication and transmission of bovine FLUDV in guinea pigs. Following direct intranasal inoculation of animals, the virus was detected in nasal washes of infected animals during the first 7 days postinfection. High viral titers were obtained from nasal turbinates and lung tissues of directly inoculated animals. Further, bovine FLUDV was able to transmit from the infected guinea pigs to sentinel animals by means of contact and not by aerosol dissemination under the experimental conditions tested in this study. Despite exhibiting no clinical signs, infected guinea pigs developed seroconversion and the viral antigen was detected in lungs of animals by immunohistochemistry. The observation that bovine FLUDV replicated in the respiratory tract of guinea pigs was similar to observations described previously in studies of gnotobiotic calves and pigs experimentally infected with bovine FLUDV but different from those described previously in experimental infections in ferrets and swine with a swine FLUDV, which supported virus replication only in the upper respiratory tract and not in the lower respiratory tract, including lung. Our study established that guinea pigs could be used as an animal model for studying this newly emerging influenza virus. Influenza D virus (FLUDV) is a novel emerging pathogen with bovine as its primary host. The epidemiology and pathogenicity of the virus are not yet known. FLUDV also spreads to swine, and the presence of FLUDV-specific antibodies in humans could indicate that there is a potential for zoonosis. Our results showed that bovine FLUDV replicated in the nasal turbinate and lungs of guinea pigs at high titers and was also able to transmit from an infected animal to sentinel animals by contact. The fact that bovine FLUDV replicated productively in both the upper and lower respiratory tracts of guinea pigs

  3. Flavone Enhances Dengue Virus Type-2 (NGC Strain Infectivity and Replication in Vero Cells

    Directory of Open Access Journals (Sweden)

    Keivan Zandi

    2012-02-01

    Full Text Available This study investigates the effects of 2-phenyl-1-benzopyran-4-one (flavone on DENV-2 infectivity in Vero cells. Virus adsorption and attachment and intracellular virus replication were investigated using a foci forming unit assay (FFUA and quantitative RT-PCR, respectively. Addition of flavone (100 μg/mL significantly increased the number of DENV-2 foci by 35.66% ± 1.52 and 49.66% ± 2.51 when added during and after virus adsorption to the Vero cells, respectively. The average foci size after 4 days of infection increased by 33% ± 2.11 and 89% ± 2.13. The DENV-2 specific RNA copy number in the flavone-treated infected cells increased by 6.41- and 23.1-fold when compared to the mock-treated infected cells. Flavone (100 μg/mL did not promote or inhibit Vero cell proliferation. The CC50 value of flavone against Vero cells was 446 µg/mL. These results suggest that flavone might enhance dengue virus replication by acting antagonistically towards flavonoids known to inhibit dengue virus replication.

  4. Replication cycle of duck hepatitis A virus type 1 in duck embryonic hepatocytes

    International Nuclear Information System (INIS)

    Yao, Fangke; Chen, Yun; Shi, Jintong; Ming, Ke; Liu, Jiaguo; Xiong, Wen; Song, Meiyun; Du, Hongxu; Wang, Yixuan; Zhang, Shuaibin; Wu, Yi; Wang, Deyun; Hu, Yuanliang

    2016-01-01

    Duck hepatitis A virus type 1 (DHAV-1) is an important agent of duck viral hepatitis. Until recently, the replication cycle of DHAV-1 is still unknown. Here duck embryonic hepatocytes infected with DHAV-1 were collected at different time points, and dynamic changes of the relative DHAV-1 gene expression during replication were detected by real-time PCR. And the morphology of hepatocytes infected with DHAV was evaluated by electron microscope. The result suggested that the adsorption of DHAV-1 saturated at 90 min post-infection, and the virus particles with size of about 50 nm including more than 20 nm of vacuum drying gold were observed on the infected cells surface. What's more, the replication lasted around 13 h after the early protein synthesis for about 5 h, and the release of DHAV-1 was in steady state after 32 h. The replication cycle will enrich the data for DVH control and provide the foundation for future studies. - Highlights: • This is the first description of the replication cycle of DHAV-1. • Firstly find that DHAV-1 adsorption saturated at 90 min post-infection. • The replication lasted around 13 h after early protein synthesis for about 5 h. • The release of DHAV-1 was in steady state after 32 h.

  5. Replication cycle of duck hepatitis A virus type 1 in duck embryonic hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Fangke; Chen, Yun; Shi, Jintong; Ming, Ke; Liu, Jiaguo, E-mail: liujiaguo@njau.edu.cn; Xiong, Wen; Song, Meiyun; Du, Hongxu; Wang, Yixuan; Zhang, Shuaibin; Wu, Yi; Wang, Deyun; Hu, Yuanliang

    2016-04-15

    Duck hepatitis A virus type 1 (DHAV-1) is an important agent of duck viral hepatitis. Until recently, the replication cycle of DHAV-1 is still unknown. Here duck embryonic hepatocytes infected with DHAV-1 were collected at different time points, and dynamic changes of the relative DHAV-1 gene expression during replication were detected by real-time PCR. And the morphology of hepatocytes infected with DHAV was evaluated by electron microscope. The result suggested that the adsorption of DHAV-1 saturated at 90 min post-infection, and the virus particles with size of about 50 nm including more than 20 nm of vacuum drying gold were observed on the infected cells surface. What's more, the replication lasted around 13 h after the early protein synthesis for about 5 h, and the release of DHAV-1 was in steady state after 32 h. The replication cycle will enrich the data for DVH control and provide the foundation for future studies. - Highlights: • This is the first description of the replication cycle of DHAV-1. • Firstly find that DHAV-1 adsorption saturated at 90 min post-infection. • The replication lasted around 13 h after early protein synthesis for about 5 h. • The release of DHAV-1 was in steady state after 32 h.

  6. [Differentiation of influenza (Flu) type A, type B, and respiratory syncytial virus (RSV) by QuickNavi™-Flu+RSV].

    Science.gov (United States)

    Kohiyama, Risa; Miyazawa, Takashi; Shibano, Nobuko; Inano, Koichi

    2014-01-01

    Because it is not easy to differentiate Influenza virus (Flu) from RS virus (RSV) just by clinical symptoms, to accurately diagnose those viruses in conjunction with patient's clinical symptoms, rapid diagnostic kits has been used separately for each of those viruses. In our new study, we have developed a new rapid diagnostic kit, QuickNavi™-Flu+RSV. The kit can detect Flu A, Flu B, and RSV antigens with a single sample collection and an assay. Total of 2,873 cases (including nasopharyngeal swabs and nasopharyngeal aspirates specimens) in 2010/2011 and 2011/2012 seasons were evaluated with QuickNavi™-Flu+RSV and a commercially available kit. Sensitivity, specificity, and accuracy of Flu type A, type B, and RSV were above 95% when compared to commercially available kits (QuickNavi™-Flu and QuickNavi™-RSV) and considered to be equivalent to the commercially available kits. In 2011/2012 season, RSV infections increased prior to Flu season and continued during the peak of the Flu season. The kit can contribute to accurate diagnosis of Flu and RSV infections since co-infection cases have also been reported during the 2011/2012 season. QuickNavi™-Flu+RSV is useful for differential diagnosis of respiratory infectious diseases since it can detect Flu type A, type B, and RSV virus antigens with a single sample collection.

  7. Zika virus preferentially replicates in the female reproductive tract after vaginal inoculation of rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Timothy Carroll

    2017-07-01

    Full Text Available Zika virus (ZIKV is a mosquito-transmitted virus that can cause severe defects in an infected fetus. ZIKV is also transmitted by sexual contact, although the relative importance of sexual transmission is unclear. To better understand the role of sexual transmission in ZIKV pathogenesis, a nonhuman primate (NHP model of vaginal transmission was developed. ZIKV was readily transmitted to mature cycling female rhesus macaque (RM by vaginal inoculation with 104-106 plaque-forming units (PFU. However, there was variability in susceptibility between the individual RM with 1->8 vaginal inoculations required to establish infection. After treatment with Depoprovera, a widely used contraceptive progestin, two RM that initially resisted 8 vaginal ZIKV inoculations became infected after one ZIKV inoculation. Thus, Depoprovera seemed to enhance susceptibility to vaginal ZIKV transmission. Unexpectedly, the kinetics of virus replication and dissemination after intravaginal ZIKV inoculation were markedly different from RM infected with ZIKV by subcutaneous (SQ virus inoculation. Several groups have reported that after SQ ZIKV inoculation vRNA is rapidly detected in blood plasma with vRNA less common in urine and saliva and only rarely detected in female reproductive tract (FRT secretions. In contrast, in vaginally inoculated RM, plasma vRNA is delayed for several days and ZIKV replication in, and vRNA shedding from, the FRT was found in all 6 animals. Further, after intravaginal transmission ZIKV RNA shedding from FRT secretions was detected before or simultaneously with plasma vRNA, and persisted for at least as long. Thus, ZIKV replication in the FRT was independent of, and often preceded virus replication in the tissues contributing to plasma vRNA. These results support the conclusion that ZIKV preferentially replicates in the FRT after vaginal transmission, but not after SQ transmission, and raise the possibility that there is enhanced fetal infection and

  8. Zika virus preferentially replicates in the female reproductive tract after vaginal inoculation of rhesus macaques.

    Science.gov (United States)

    Carroll, Timothy; Lo, Ming; Lanteri, Marion; Dutra, Joseph; Zarbock, Katie; Silveira, Paola; Rourke, Tracy; Ma, Zhong-Min; Fritts, Linda; O'Connor, Shelby; Busch, Michael; Miller, Christopher J

    2017-07-01

    Zika virus (ZIKV) is a mosquito-transmitted virus that can cause severe defects in an infected fetus. ZIKV is also transmitted by sexual contact, although the relative importance of sexual transmission is unclear. To better understand the role of sexual transmission in ZIKV pathogenesis, a nonhuman primate (NHP) model of vaginal transmission was developed. ZIKV was readily transmitted to mature cycling female rhesus macaque (RM) by vaginal inoculation with 104-106 plaque-forming units (PFU). However, there was variability in susceptibility between the individual RM with 1->8 vaginal inoculations required to establish infection. After treatment with Depoprovera, a widely used contraceptive progestin, two RM that initially resisted 8 vaginal ZIKV inoculations became infected after one ZIKV inoculation. Thus, Depoprovera seemed to enhance susceptibility to vaginal ZIKV transmission. Unexpectedly, the kinetics of virus replication and dissemination after intravaginal ZIKV inoculation were markedly different from RM infected with ZIKV by subcutaneous (SQ) virus inoculation. Several groups have reported that after SQ ZIKV inoculation vRNA is rapidly detected in blood plasma with vRNA less common in urine and saliva and only rarely detected in female reproductive tract (FRT) secretions. In contrast, in vaginally inoculated RM, plasma vRNA is delayed for several days and ZIKV replication in, and vRNA shedding from, the FRT was found in all 6 animals. Further, after intravaginal transmission ZIKV RNA shedding from FRT secretions was detected before or simultaneously with plasma vRNA, and persisted for at least as long. Thus, ZIKV replication in the FRT was independent of, and often preceded virus replication in the tissues contributing to plasma vRNA. These results support the conclusion that ZIKV preferentially replicates in the FRT after vaginal transmission, but not after SQ transmission, and raise the possibility that there is enhanced fetal infection and pathology

  9. Internal Disequilibria and Phenotypic Diversification during Replication of Hepatitis C Virus in a Noncoevolving Cellular Environment.

    Science.gov (United States)

    Moreno, Elena; Gallego, Isabel; Gregori, Josep; Lucía-Sanz, Adriana; Soria, María Eugenia; Castro, Victoria; Beach, Nathan M; Manrubia, Susanna; Quer, Josep; Esteban, Juan Ignacio; Rice, Charles M; Gómez, Jordi; Gastaminza, Pablo; Domingo, Esteban; Perales, Celia

    2017-05-15

    Viral quasispecies evolution upon long-term virus replication in a noncoevolving cellular environment raises relevant general issues, such as the attainment of population equilibrium, compliance with the molecular-clock hypothesis, or stability of the phenotypic profile. Here, we evaluate the adaptation, mutant spectrum dynamics, and phenotypic diversification of hepatitis C virus (HCV) in the course of 200 passages in human hepatoma cells in an experimental design that precluded coevolution of the cells with the virus. Adaptation to the cells was evidenced by increase in progeny production. The rate of accumulation of mutations in the genomic consensus sequence deviated slightly from linearity, and mutant spectrum analyses revealed a complex dynamic of mutational waves, which was sustained beyond passage 100. The virus underwent several phenotypic changes, some of which impacted the virus-host relationship, such as enhanced cell killing, a shift toward higher virion density, and increased shutoff of host cell protein synthesis. Fluctuations in progeny production and failure to reach population equilibrium at the genomic level suggest internal instabilities that anticipate an unpredictable HCV evolution in the complex liver environment. IMPORTANCE Long-term virus evolution in an unperturbed cellular environment can reveal features of virus evolution that cannot be explained by comparing natural viral isolates. In the present study, we investigate genetic and phenotypic changes that occur upon prolonged passage of hepatitis C virus (HCV) in human hepatoma cells in an experimental design in which host cell evolutionary change is prevented. Despite replication in a noncoevolving cellular environment, the virus exhibited internal population disequilibria that did not decline with increased adaptation to the host cells. The diversification of phenotypic traits suggests that disequilibria inherent to viral populations may provide a selective advantage to viruses that can

  10. Endogenous hepatitis C virus homolog fragments in European rabbit and hare genomes replicate in cell culture.

    Directory of Open Access Journals (Sweden)

    Eliane Silva

    Full Text Available Endogenous retroviruses, non-retroviral RNA viruses and DNA viruses have been found in the mammalian genomes. The origin of Hepatitis C virus (HCV, the major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma in humans, remains unclear since its discovery. Here we show that fragments homologous to HCV structural and non-structural (NS proteins present in the European rabbit (Oryctolagus cuniculus and hare (Lepus europaeus genomes replicate in bovine cell cultures. The HCV genomic homolog fragments were demonstrated by RT-PCR, PCR, mass spectrometry, and replication in bovine cell cultures by immunofluorescence assay (IFA and immunogold electron microscopy (IEM using specific MAbs for HCV NS3, NS4A, and NS5 proteins. These findings may lead to novel research approaches on the HCV origin, genesis, evolution and diversity.

  11. Comparison of the Simplexa™ Flu A/B & RSV kit (nucleic acid extraction-dependent assay) and the Prodessa ProFlu+™ assay for detecting influenza and respiratory syncytial viruses.

    Science.gov (United States)

    Selvaraju, Suresh B; Bambach, Adrienne V; Leber, Amy L; Patru, Maria-Magdalena; Patel, Anami; Menegus, Marilyn A

    2014-09-01

    The relative performance of 2 widely used reverse transcription polymerase chain reaction (RT-PCR) assays, the Focus diagnostics Simplexa™ Flu A/B & RSV kit (nucleic acid extraction-dependent assay) and the Prodessa Proflu+™ assay, was evaluated using 735 prospectively and retrospectively collected nasopharyngeal swab specimens. Overall, the assays showed positive and negative agreements of 100% and 99.7% for influenza A, 98.1% and 99.9% for influenza B, and 99.3% and 99.5% for respiratory syncytial virus. The relative analytical sensitivity of the 2 assays was also similar. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Use of palivizumab and infection control measures to control an outbreak of respiratory syncytial virus in a neonatal intensive care unit confirmed by real-time polymerase chain reaction.

    LENUS (Irish Health Repository)

    O'Connell, K

    2011-04-01

    Respiratory syncytial virus (RSV) is a potentially life-threatening infection in premature infants. We report an outbreak involving four infants in the neonatal intensive care unit (NICU) of our hospital that occurred in February 2010. RSV A infection was confirmed by real-time polymerase chain reaction. Palivizumab was administered to all infants in the NICU. There were no additional symptomatic cases and repeat RSV surveillance confirmed that there was no further cross-transmission within the unit. The outbreak highlighted the infection control challenge of very high bed occupancy in the unit and the usefulness of molecular methods in facilitating detection and management.

  13. Multiple Functional Domains and Complexes of the Two Nonstructural Proteins of Human Respiratory Syncytial Virus Contribute to Interferon Suppression and Cellular Location▿

    Science.gov (United States)

    Swedan, Samer; Andrews, Joel; Majumdar, Tanmay; Musiyenko, Alla; Barik, Sailen

    2011-01-01

    Human respiratory syncytial virus (RSV), a major cause of severe respiratory diseases, efficiently suppresses cellular innate immunity, represented by type I interferon (IFN), using its two unique nonstructural proteins, NS1 and NS2. In a search for their mechanism, NS1 was previously shown to decrease levels of TRAF3 and IKKε, whereas NS2 interacted with RIG-I and decreased TRAF3 and STAT2. Here, we report on the interaction, cellular localization, and functional domains of these two proteins. We show that recombinant NS1 and NS2, expressed in lung epithelial A549 cells, can form homo- as well as heteromers. Interestingly, when expressed alone, substantial amounts of NS1 and NS2 localized to the nuclei and to the mitochondria, respectively. However, when coexpressed with NS2, as in RSV infection, NS1 could be detected in the mitochondria as well, suggesting that the NS1-NS2 heteromer localizes to the mitochondria. The C-terminal tetrapeptide sequence, DLNP, common to both NS1 and NS2, was required for some functions, but not all, whereas only the NS1 N-terminal region was important for IKKε reduction. Finally, NS1 and NS2 both interacted specifically with host microtubule-associated protein 1B (MAP1B). The contribution of MAP1B in NS1 function was not tested, but in NS2 it was essential for STAT2 destruction, suggesting a role of the novel DLNP motif in protein-protein interaction and IFN suppression. PMID:21795342

  14. A single intranasal immunization with a subunit vaccine formulation induces higher mucosal IgA production than live respiratory syncytial virus

    International Nuclear Information System (INIS)

    Garg, Ravendra; Theaker, Michael; Martinez, Elisa C.; Drunen Littel-van den Hurk, Sylvia van

    2016-01-01

    Respiratory syncytial virus (RSV) causes serious respiratory illness in infants and elderly. RSV infection induces short-lived immunity, which leaves people prone to re-infection. In contrast, the RSV fusion (F) protein formulated with a novel adjuvant (∆F/TriAdj) elicits long term protective immunity. A comparison of RSV-immunized mice to mice vaccinated with a single dose of ∆F/TriAdj showed no difference in IgG1 and IgG2a production; however, local IgA secreting memory B cell development and B cell IgA production were significantly lower in RSV vaccinated mice than in ∆F/TriAdj-immunized mice. This indicates a potential reason as to why long-term immunity is not induced by RSV infection. The comparison also revealed that germinal center lymphocyte populations were higher in ∆F/TriAdj-vaccinated mice. Furthermore, ∆F/TriAdj induced higher gene expression of activation-induced cytidine deaminase (AID), as well as IL-6, IL-21, TGF-β cytokines, which are key players in IgA class switch recombination, ultimately leading to a sustained long-term memory response. - Highlights: •Immune responses to adjuvanted RSV F protein, ∆F/TriAdj, and RSV were compared. •∆F/TriAdj stimulates more local IgA production than RSV. •∆F/TriAdj induces more local IgA secreting memory B cells than RSV. •Germinal center lymphocyte populations are higher in ∆F/TriAdj-vaccinated mice. •∆F/TriAdj induces higher gene expression of AID, IL-6, IL-21, and TGF-β than RSV.

  15. [Prevalence of respiratory syncytial virus infection in hospitalized children at a children's hospital and effects of climate change on the prevalence in Suzhou, China].

    Science.gov (United States)

    Geng, Jia; Guo, Wan-Liang; Zhang, Xue-Lan

    2015-05-01

    To investigate the prevalence of respiratory syncytial virus (RSV) infection in hospitalized children and the relationship between the prevalence and the climate change in Suzhou, China. A total of 42 664 nasopharyngeal secretions from hospitalized children with acute respiratory infection at the Suzhou Children's Hospital were screened for RSV antigens using direct immunofluorescence. Monthly meteorological data (mean monthly air temperature, monthly relative humidity, monthly rainfall, total monthly sunshine duration, and mean monthly wind velocity) in Suzhou between 2001 and 2011 were collected. The correlations between RSV detection rate and climatic factors were evaluated using correlation and stepwise regression analysis. The annual RSV infection rate in hospitalized children with respiratory infection in the Suzhou Children's Hospital varied between 11.85% and 27.30% from 2001 to 2011. In the 9 epidemic seasons, each spanning from November to April of the next year, from 2001 to 2010, the RSV detection rates were 40.75%, 22.72%, 39.93%, 27.37%, 42.71%, 21.28%, 38.57%, 19.86%, and 29.73%, respectively; there were significant differences in the detection rate between the epidemic seasons. The monthly RSV detection rate was negatively correlated with mean monthly air temperature, total monthly sunshine duration, monthly rainfall, monthly relative humidity, and mean monthly wind velocity (P<0.05). Stepwise regression analysis showed that mean monthly air temperature fitted into a linear model (R(2)=0.64, P<0.01). From 2001 to 2011, RSV infection in Suzhou was predominantly prevalent between November and April of the next year. As a whole, the infection rate of RSV reached a peak every other year. Air temperature played an important role in the epidemics of RSV infection in Suzhou.

  16. Water extract of Pueraria lobata Ohwi has anti-viral activity against human respiratory syncytial virus in human respiratory tract cell lines

    Directory of Open Access Journals (Sweden)

    Tzeng-Jih Lin

    2013-12-01

    Full Text Available Human respiratory syncytial virus (HRSV infects all age groups and causes bronchiolitis, pneumonia, and acute respiratory distress syndrome with a significant mortality rate. To date, only ribavirin has been used to manage HRSV infection. However, ribavirin is expensive with an only modest effect. Furthermore, ribavirin has several side effects, which means it has limited clinical benefit. Pueraria lobata Ohwi (P. lobata is a common ingredient of Ge-Gen-Tang (Kakkon-to and Sheng-Ma-Ge-Gen-Tang (Shoma-kakkon-to, which are prescriptions of Chinese traditional medicine proven to have antiviral activity against HRSV. Therefore, it was hypothesized that P. lobata might be effective against HRSV. To find a cost-effective therapeutic modality, both human upper (HEp-2 and lower (A549 respiratory tract cell lines were used to test the hypothesis that P. lobata could inhibit HRSV-induced plaque formation. Results showed that the water extract of P. lobata was effective (p < 0.0001 against HRSV-induced plaque formation. P. lobata was more effective when given prior to viral inoculation (p < 0.0001 by inhibiting viral attachment (p < 0.0001 and penetration (p < 0.0001. However, supplementation with P. lobata could not stimulate interferon secretion after HRSV infection. In conclusion, P. lobata has antiviral activity against HRSV-induced plaque formation in airway mucosa mainly by inhibiting viral attachment and internalization. Further identification of effective constituents could contribute to the prevention of HRSV infection.

  17. A single intranasal immunization with a subunit vaccine formulation induces higher mucosal IgA production than live respiratory syncytial virus

    Energy Technology Data Exchange (ETDEWEB)

    Garg, Ravendra [VIDO-InterVac, University of Saskatchewan, Saskatoon, SK S7N 5E3 (Canada); Theaker, Michael [Microbiology & Immunology, University of Saskatchewan, Saskatoon, SK S7N 5E3 (Canada); Martinez, Elisa C. [VIDO-InterVac, University of Saskatchewan, Saskatoon, SK S7N 5E3 (Canada); Microbiology & Immunology, University of Saskatchewan, Saskatoon, Canada SK S7N 5E3 (Canada); Drunen Littel-van den Hurk, Sylvia van, E-mail: sylvia.vandenhurk@usask.ca [VIDO-InterVac, University of Saskatchewan, Saskatoon, SK S7N 5E3 (Canada); Microbiology & Immunology, University of Saskatchewan, Saskatoon, SK S7N 5E3 (Canada)

    2016-12-15

    Respiratory syncytial virus (RSV) causes serious respiratory illness in infants and elderly. RSV infection induces short-lived immunity, which leaves people prone to re-infection. In contrast, the RSV fusion (F) protein formulated with a novel adjuvant (∆F/TriAdj) elicits long term protective immunity. A comparison of RSV-immunized mice to mice vaccinated with a single dose of ∆F/TriAdj showed no difference in IgG1 and IgG2a production; however, local IgA secreting memory B cell development and B cell IgA production were significantly lower in RSV vaccinated mice than in ∆F/TriAdj-immunized mice. This indicates a potential reason as to why long-term immunity is not induced by RSV infection. The comparison also revealed that germinal center lymphocyte populations were higher in ∆F/TriAdj-vaccinated mice. Furthermore, ∆F/TriAdj induced higher gene expression of activation-induced cytidine deaminase (AID), as well as IL-6, IL-21, TGF-β cytokines, which are key players in IgA class switch recombination, ultimately leading to a sustained long-term memory response. - Highlights: •Immune responses to adjuvanted RSV F protein, ∆F/TriAdj, and RSV were compared. •∆F/TriAdj stimulates more local IgA production than RSV. •∆F/TriAdj induces more local IgA secreting memory B cells than RSV. •Germinal center lymphocyte populations are higher in ∆F/TriAdj-vaccinated mice. •∆F/TriAdj induces higher gene expression of AID, IL-6, IL-21, and TGF-β than RSV.

  18. Humane metapneumovirus (HMPV) associated pulmonary infections in immunocompromised adults—Initial CT findings, disease course and comparison to respiratory-syncytial-virus (RSV) induced pulmonary infections

    International Nuclear Information System (INIS)

    Syha, R.; Beck, R.; Hetzel, J.; Ketelsen, D.; Grosse, U.; Springer, F.; Horger, M.

    2012-01-01

    Aim: To describe computed tomography (CT)-imaging findings in human metapneumovirus (HMPV)-related pulmonary infection as well as their temporal course and to analyze resemblances/differences to pulmonary infection induced by the closely related respiratory-syncytial-virus (RSV) in immunocompromised patients. Materials and methods: Chest-CT-scans of 10 HMPV PCR-positive patients experiencing pulmonary symptoms were evaluated retrospectively with respect to imaging findings and their distribution and results were then compared with data acquired in 13 patients with RSV pulmonary infection. Subsequently, we analyzed the course of chest-findings in HMPV patients. Results: In HMPV, 8/10 patients showed asymmetric pulmonary findings, whereas 13/13 patients with RSV-pneumonia presented more symmetrical bilateral pulmonary infiltrates. Image analysis yielded in HMPV patients following results: ground-glass-opacity (GGO) (n = 6), parenchymal airspace consolidations (n = 5), ill-defined nodular-like centrilobular opacities (n = 9), bronchial wall thickening (n = 8). In comparison, results in RSV patients were: GGO (n = 10), parenchymal airspace consolidations (n = 9), ill-defined nodular-like centrilobular opacities (n = 10), bronchial wall thickening (n = 4). In the course of the disease, signs of acute HMPV interstitial pneumonia regressed transforming temporarily in part into findings compatible with bronchitis/bronchiolitis. Conclusions: Early chest-CT findings in patients with HMPV-related pulmonary symptoms are compatible with asymmetric acute interstitial pneumonia accompanied by signs of bronchitis; the former transforming with time into bronchitis and bronchiolitis before they resolve. On the contrary, RSV-induced pulmonary infection exhibits mainly symmetric acute interstitial pneumonia.

  19. Risk factors of respiratory syncytial virus infection among pediatric influenza-like illness and severe acute respiratory infections in Suzhou, China.

    Science.gov (United States)

    Huang, Yukai; Hua, Jun; Wang, Dan; Chen, Liling; Zhang, Jun; Zhu, Hong; Tian, Jianmei; Zhang, Tao; Zhao, Genming

    2018-03-01

    The characteristics and risk factors of respiratory syncytial virus (RSV) infection among children has not yet been fully understood. To address the characteristics of RSV-associated illness and risk factors of RSV infection among children under 5 years of age in Suzhou, China. From April 2011 to March 2014, we conducted a prospective surveillance among children in Suzhou, China. Nasal or throat swabs were collected from outpatients with influenza-like illness (ILI) and inpatients with severe acute respiratory infections (SARI). RSV was detected by reverse-transcriptase polymerase chain reaction and direct fluorescent antibody assay for children with ILI and SARI, respectively. Multivariable logistic-regression models were constructed to explore risk factors and symptoms of RSV infection. Of 3267 ILI and 1838 SARI children enrolled in the study, 192 (5.9%) and 287 (15.6%) tested positive for RSV, respectively. Among ILI patients, children with RSV infections visited clinics more often (P = 0.005) and had longer duration of fever (P = 0.032) than those without RSV infection. All RSV-positive children had an increased risk of having cough (OR = 2.9), rhinorrhea (OR = 1.6), breathing difficulty (OR = 3.4), wheezing (OR = 3.3), and irritability (OR = 2.7). Children aged respiratory infections (OR = 1.3) were more likely to get infected by RSV. Children with SARI had higher positive rate of RSV than those with ILI. Cough, rhinorrhea, and wheezing were the most common symptoms in RSV infection. Children aged respiratory infections were the potential risk factors for RSV infection. © 2017 Wiley Periodicals, Inc.

  20. Humane metapneumovirus (HMPV) associated pulmonary infections in immunocompromised adults—Initial CT findings, disease course and comparison to respiratory-syncytial-virus (RSV) induced pulmonary infections

    Energy Technology Data Exchange (ETDEWEB)

    Syha, R., E-mail: roland.syha@med.uni-tuebingen.de [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen (Germany); Beck, R. [Institute of Medical Virology, Eberhard-Karls-University, Elfriede-Authorn-Str. 6, 72076 Tübingen (Germany); Hetzel, J. [Department of Medical Oncology and Hematology, Eberhard-Karls-University, Otfried-Müller-Str. 10, 72070 Tübingen (Germany); Ketelsen, D.; Grosse, U.; Springer, F.; Horger, M. [Department of Diagnostic Radiology, Eberhard-Karls-University, Hoppe-Seyler-Str.3, 72076 Tübingen (Germany)

    2012-12-15

    Aim: To describe computed tomography (CT)-imaging findings in human metapneumovirus (HMPV)-related pulmonary infection as well as their temporal course and to analyze resemblances/differences to pulmonary infection induced by the closely related respiratory-syncytial-virus (RSV) in immunocompromised patients. Materials and methods: Chest-CT-scans of 10 HMPV PCR-positive patients experiencing pulmonary symptoms were evaluated retrospectively with respect to imaging findings and their distribution and results were then compared with data acquired in 13 patients with RSV pulmonary infection. Subsequently, we analyzed the course of chest-findings in HMPV patients. Results: In HMPV, 8/10 patients showed asymmetric pulmonary findings, whereas 13/13 patients with RSV-pneumonia presented more symmetrical bilateral pulmonary infiltrates. Image analysis yielded in HMPV patients following results: ground-glass-opacity (GGO) (n = 6), parenchymal airspace consolidations (n = 5), ill-defined nodular-like centrilobular opacities (n = 9), bronchial wall thickening (n = 8). In comparison, results in RSV patients were: GGO (n = 10), parenchymal airspace consolidations (n = 9), ill-defined nodular-like centrilobular opacities (n = 10), bronchial wall thickening (n = 4). In the course of the disease, signs of acute HMPV interstitial pneumonia regressed transforming temporarily in part into findings compatible with bronchitis/bronchiolitis. Conclusions: Early chest-CT findings in patients with HMPV-related pulmonary symptoms are compatible with asymmetric acute interstitial pneumonia accompanied by signs of bronchitis; the former transforming with time into bronchitis and bronchiolitis before they resolve. On the contrary, RSV-induced pulmonary infection exhibits mainly symmetric acute interstitial pneumonia.

  1. Epidemiology, clinical characteristics, laboratory findings and severity of respiratory syncytial virus acute lower respiratory infection in Malaysian children, 2008-2013.

    Science.gov (United States)

    Ng, Khuen F; Tan, Kah K; Sam, Zhi H; Ting, Grace Ss; Gan, Wan Y

    2017-04-01

    The aim of this study is to describe epidemiology, clinical features, laboratory data and severity of respiratory syncytial virus (RSV) acute lower respiratory infection (ALRI) in Malaysian children and to determine risk factors associated with prolonged hospital stay, paediatric intensive care unit (PICU) admission and mortality. Retrospective data on demographics, clinical presentation, outcomes and laboratory findings of 450 children admitted into Tuanku Jaafar Hospital in Seremban, Malaysia from 2008 to 2013 with documented diagnosis of RSV ALRI were collected and analysed. Most admissions were children below 2 years old (85.8%; 386/450). Commonest symptoms were fever (84.2%; 379/450), cough (97.8%; 440/450) and rhinorrhea (83.6%; 376/450). The median age among febrile patients (n = 379) was 9.0 months with interquartile range (IQR) of 4.0-19.0 months whereas the median age among those who were apyrexial (n = 71) was 2 months with IQR of 1-6 months (P-value <0.001). 15.3% (69/450) needed intensive care and 1.6% (7/450) died. Young age, history of prematurity, chronic comorbidity and thrombocytosis were significantly associated with prolonged hospital stay, PICU admission and mortality. Infants less than 6 months old with RSV ALRI tend to be afebrile at presentation. Younger age, history of prematurity, chronic comorbidity and thrombocytosis are predictors of severe RSV ALRI among Malaysian children. Case fatality rate for Malaysian children below 5 years of age with RSV ALRI in our centre is higher than what is seen in developed countries, suggesting that there is room for improvement. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  2. A prospective, open-label, non-comparative study of palivizumab prophylaxis in children at high risk of serious respiratory syncytial virus disease in the Russian Federation

    Directory of Open Access Journals (Sweden)

    Turti Tatyana V

    2012-09-01

    Full Text Available Abstract Background Respiratory syncytial virus (RSV is a leading cause of lower respiratory tract infections (LRTIs in children globally. Predisposing conditions for the development of serious RSV disease include preterm infants and those with cardiopulmonary illness, including congenital heart disease (CHD and bronchopulmonary dysplasia (BPD. No vaccine is currently approved for the prevention of RSV infection. It is recommended that children at high risk be prophylactically administered palivizumab, a monoclonal antibody that has been shown in a number of clinical studies to reduce hospitalization rates due to serious RSV infection. The objective of the current study was to determine the safety and effectiveness of palivizumab in preventing serious RSV disease in high-risk children in the Russian Federation. Children at high risk of serious RSV disease (ie, born at ≤35 wk gestational age and ≤6 mo of age, and/or aged ≤24 mo with BPD or hemodynamically significant CHD were enrolled. Subjects were to receive 3 to 5 monthly injections of palivizumab 15 mg/kg (depending on the month of the initial injection over the RSV season. The primary endpoint was RSV-related hospitalizations. Adverse events (AEs were reported through 100 days following the final injection. Results One hundred subjects received ≥1 injection of palivizumab; 94 completed their dosing schedule. There were no RSV hospitalizations or deaths. Six of 7 subjects hospitalized for respiratory/cardiac conditions had an RSV test, which was negative in all cases. Three non-serious AEs (acute intermittent rhinitis and rhinitis, 1 subject; atopic dermatitis, 1 subject were considered possibly related to palivizumab. All other AEs were mild or moderate and considered not related/probably not related to palivizumab. Conclusion Palivizumab was generally well tolerated and effectively prevented serious RSV infection in a mixed population of high-risk children in the Russian

  3. Genetic variability of human respiratory syncytial virus A strains circulating in Ontario: a novel genotype with a 72 nucleotide G gene duplication.

    Directory of Open Access Journals (Sweden)

    Alireza Eshaghi

    Full Text Available Human respiratory syncytial virus (HRSV is the main cause of acute lower respiratory infections in children under 2 years of age and causes repeated infections throughout life. We investigated the genetic variability of RSV-A circulating in Ontario during 2010-2011 winter season by sequencing and phylogenetic analysis of the G glycoprotein gene.Among the 201 consecutive RSV isolates studied, RSV-A (55.7% was more commonly observed than RSV-B (42.3%. 59.8% and 90.1% of RSV-A infections were among children ≤12 months and ≤5 years old, respectively. On phylogenetic analysis of the second hypervariable region of the 112 RSV-A strains, 110 (98.2% clustered within or adjacent to the NA1 genotype; two isolates were GA5 genotype. Eleven (10% NA1-related isolates clustered together phylogenetically as a novel RSV-A genotype, named ON1, containing a 72 nucleotide duplication in the C-terminal region of the attachment (G glycoprotein. The predicted polypeptide is lengthened by 24 amino acids and includes a23 amino acid duplication. Using RNA secondary structural software, a possible mechanism of duplication occurrence was derived. The 23 amino acid ON1 G gene duplication results in a repeat of 7 potential O-glycosylation sites including three O-linked sugar acceptors at residues 270, 275, and 283. Using Phylogenetic Analysis by Maximum Likelihood analysis, a total of 19 positively selected sites were observed among Ontario NA1 isolates; six were found to be codons which reverted to the previous state observed in the prototype RSV-A2 strain. The tendency of codon regression in the G-ectodomain may infer a decreased avidity of antibody to the current circulating strains. Further work is needed to document and further understand the emergence, virulence, pathogenicity and transmissibility of this novel RSV-A genotype with a72 nucleotide G gene duplication.

  4. Molecular characterization of circulating respiratory syncytial virus (RSV genotypes in Gilgit Baltistan Province of Pakistan during 2011-2012 winter season.

    Directory of Open Access Journals (Sweden)

    Uzma Bashir

    Full Text Available Respiratory syncytial virus (RSV is the major cause of acute lower respiratory tract infections in young children, but very little is known about its epidemiology and circulating genotypes in Pakistan. This study analyzed the epidemiological and molecular characteristics of RSV genotypes detected in Pakistani children less than 2 years of age with acute respiratory tract infections (ARIs in a tertiary care hospital in Gilgit Baltistan (GB province during 2011-12 winter season. RSV was detected in 75 out of 105 children presenting with acute respiratory infection. Male infants between 2-6 months age made up the highest percentage of RSV positive cases. Epidemiological factors such as pre-maturity, mean weight, clinical features and diagnosis when compared between RSV positive and negative groups were found to be statistically insignificant. Phylogenetic analysis classified all 75 of the RSV strains into 71 strains of subgroups A and 4 strains of subgroup B, respectively. Strains belonging to subgroups A and B were further subdivided into NA1/GA2 and BA, respectively. The nucleotide and deduced amino acid sequence identities were relatively high among these strains (>90%. Both RSV-A and RSV-B isolates had two potential N-glycosylation sites in HVR2 of G protein and with heavy O-glycosylation of serine and threonine residues (G scores of 0.5-0.7. This report highlights the significance of RSV as a dominant viral etiologic agent of pediatric ARIs, and need for continued molecular epidemiological surveys for early detection of prevalent strains and newly emerging genotypes to understand epidemiology of RSV infections in various regions of Pakistan.

  5. Influence of the Leader protein coding region of foot-and-mouth disease virus on virus replication

    DEFF Research Database (Denmark)

    Belsham, Graham

    2013-01-01

    The foot-and-mouth disease virus (FMDV) Leader (L) protein is produced in two forms, Lab and Lb, differing only at their amino-termini, due to the use of separate initiation codons, usually 84 nt apart. It has been shown previously, and confirmed here, that precise deletion of the Lab coding......, in the context of the virus lacking the Lb coding region, was also tolerated by the virus within BHK cells. However, precise loss of the Lb coding sequence alone blocked FMDV replication in primary bovine thyroid cells. Thus, the requirement for the Leader protein coding sequences is highly dependent...... on the nature and extent of the residual Leader protein sequences and on the host cell system used. FMDVs precisely lacking Lb and with the Lab initiation codon modified may represent safer seed viruses for vaccine production....

  6. Relationship between RNA polymerase II and efficiency of vaccinia virus replication

    International Nuclear Information System (INIS)

    Wilton, S.; Dales, S.

    1989-01-01

    It is clear from previous studies that host transcriptase or RNA polymerase II (pol II) has a role in poxvirus replication. To elucidate the participation of this enzyme further, in this study the authors examined several parameters related to pol II during the cycle of vaccinia virus infection in L-strain fibroblasts, HeLa cells, and L 6 H 9 rat myoblasts. Nucleocytoplasmic transposition of pol II into virus factories and virions was assessed by immunofluorescence and immunoblotting by using anti-pol II immunoglobulin G. RNA polymerase activities were compared in nuclear extracts containing cured enzyme preparations. Rates of translation into cellular or viral polypeptides were ascertained by labeling with [ 35 S]methionine. In L and HeLa cells, which produced vaccinia virus more abundantly, the rate of RNA polymerase and translation in controls and following infection were higher than in myoblasts. The data on synthesis and virus formation could be correlated with observations on transmigration of pol II, which was more efficient and complete in L and HeLa cells. The stimulus for pol II to leave the nucleus required the expression of both early and late viral functions. On the basis of current and past information, the authors suggest that mobilization of pol II depends on the efficiency of vaccinia virus replication and furthermore that control over vaccinia virus production by the host is related to the content or availability (or both) of pol II in different cell types

  7. Fatty acid translocase promoted hepatitis B virus replication by upregulating the levels of hepatic cytosolic calcium.

    Science.gov (United States)

    Huang, Jian; Zhao, Lei; Yang, Ping; Chen, Zhen; Ruan, Xiong Z; Huang, Ailong; Tang, Ni; Chen, Yaxi

    2017-09-15

    Hepatitis B virus (HBV) is designated a "metabolovirus" due to the intimate connection between the virus and host metabolism. The nutrition state of the host plays a relevant role in the severity of HBV infection. Metabolic syndrome (MS) is prone to increasing HBV DNA loads and accelerating the progression of liver disease in patients with chronic hepatitis B (CHB). Cluster of differentiation 36 (CD36), also named fatty acid translocase, is known to facilitate long-chain fatty acid uptake and contribute to the development of MS. We recently found that CD36 overexpression enhanced HBV replication. In this study, we further explored the mechanism by which CD36 overexpression promotes HBV replication. Our data showed that CD36 overexpression increased HBV replication, and CD36 knockdown inhibited HBV replication. RNA sequencing found some of the differentially expressed genes were involved in calcium ion homeostasis. CD36 overexpression elevated the cytosolic calcium level, and CD36 knockdown decreased the cytosolic calcium level. Calcium chelator BAPTA-AM could override the HBV replication increased by CD36 overexpression, and the calcium activator thapsigargin could improve the HBV replication reduced by CD36 knockdown. We further found that CD36 overexpression activated Src kinase, which plays an important role in the regulation of the store-operated Ca 2+ channel. An inhibitor of Src kinase (SU6656) significantly reduced the CD36-induced HBV replication. We identified a novel link between CD36 and HBV replication, which is associated with cytosolic calcium and the Src kinase pathway. CD36 may represent a potential therapeutic target for the treatment of CHB patients with MS. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Early low-titer neutralizing antibodies impede HIV-1 replication and select for virus escape.

    Directory of Open Access Journals (Sweden)

    Katharine J Bar

    Full Text Available Single genome sequencing of early HIV-1 genomes provides a sensitive, dynamic assessment of virus evolution and insight into the earliest anti-viral immune responses in vivo. By using this approach, together with deep sequencing, site-directed mutagenesis, antibody adsorptions and virus-entry assays, we found evidence in three subjects of neutralizing antibody (Nab responses as early as 2 weeks post-seroconversion, with Nab titers as low as 1∶20 to 1∶50 (IC(50 selecting for virus escape. In each of the subjects, Nabs targeted different regions of the HIV-1 envelope (Env in a strain-specific, conformationally sensitive manner. In subject CH40, virus escape was first mediated by mutations in the V1 region of the Env, followed by V3. HIV-1 specific monoclonal antibodies from this subject mapped to an immunodominant region at the base of V3 and exhibited neutralizing patterns indistinguishable from polyclonal antibody responses, indicating V1-V3 interactions within the Env trimer. In subject CH77, escape mutations mapped to the V2 region of Env, several of which selected for alterations of glycosylation. And in subject CH58, escape mutations mapped to the Env outer domain. In all three subjects, initial Nab recognition was followed by sequential rounds of virus escape and Nab elicitation, with Nab escape variants exhibiting variable costs to replication fitness. Although delayed in comparison with autologous CD8 T-cell responses, our findings show that Nabs appear earlier in HIV-1 infection than previously recognized, target diverse sites on HIV-1 Env, and impede virus replication at surprisingly low titers. The unexpected in vivo sensitivity of early transmitted/founder virus to Nabs raises the possibility that similarly low concentrations of vaccine-induced Nabs could impair virus acquisition in natural HIV-1 transmission, where the risk of infection is low and the number of viruses responsible for transmission and productive clinical

  9. Analysis of JC virus DNA replication using a quantitative and high-throughput assay

    Science.gov (United States)

    Shin, Jong; Phelan, Paul J.; Chhum, Panharith; Bashkenova, Nazym; Yim, Sung; Parker, Robert; Gagnon, David; Gjoerup, Ole; Archambault, Jacques; Bullock, Peter A.

    2015-01-01

    Progressive Multifocal Leukoencephalopathy (PML) is caused by lytic replication of JC virus (JCV) in specific cells of the central nervous system. Like other polyomaviruses, JCV encodes a large T-antigen helicase needed for replication of the viral DNA. Here, we report the development of a luciferase-based, quantitative and high-throughput assay of JCV DNA replication in C33A cells, which, unlike the glial cell lines Hs 683 and U87, accumulate high levels of nuclear T-ag needed for robust replication. Using this assay, we investigated the requirement for different domains of T-ag, and for specific sequences within and flanking the viral origin, in JCV DNA replication. Beyond providing validation of the assay, these studies revealed an important stimulatory role of the transcription factor NF1 in JCV DNA replication. Finally, we show that the assay can be used for inhibitor testing, highlighting its value for the identification of antiviral drugs targeting JCV DNA replication. PMID:25155200

  10. Mapping vaccinia virus DNA replication origins at nucleotide level by deep sequencing.

    Science.gov (United States)

    Senkevich, Tatiana G; Bruno, Daniel; Martens, Craig; Porcella, Stephen F; Wolf, Yuri I; Moss, Bernard

    2015-09-01

    Poxviruses reproduce in the host cytoplasm and encode most or all of the enzymes and factors needed for expression and synthesis of their double-stranded DNA genomes. Nevertheless, the mode of poxvirus DNA replication and the nature and location of the replication origins remain unknown. A current but unsubstantiated model posits only leading strand synthesis starting at a nick near one covalently closed end of the genome and continuing around the other end to generate a concatemer that is subsequently resolved into unit genomes. The existence of specific origins has been questioned because any plasmid can replicate in cells infected by vaccinia virus (VACV), the prototype poxvirus. We applied directional deep sequencing of short single-stranded DNA fragments enriched for RNA-primed nascent strands isolated from the cytoplasm of VACV-infected cells to pinpoint replication origins. The origins were identified as the switching points of the fragment directions, which correspond to the transition from continuous to discontinuous DNA synthesis. Origins containing a prominent initiation point mapped to a sequence within the hairpin loop at one end of the VACV genome and to the same sequence within the concatemeric junction of replication intermediates. These findings support a model for poxvirus genome replication that involves leading and lagging strand synthesis and is consistent with the requirements for primase and ligase activities as well as earlier electron microscopic and biochemical studies implicating a replication origin at the end of the VACV genome.

  11. Nrf2-dependent induction of innate host defense via heme oxygenase-1 inhibits Zika virus replication

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hanxia; Falgout, Barry; Takeda, Kazuyo [Food and Drug Administration, Silver Spring, MD (United States); Yamada, Kenneth M. [National Institutes of Health, Bethesda, MD (United States); Dhawan, Subhash, E-mail: subhash.dhawan@fda.hhs.gov [Food and Drug Administration, Silver Spring, MD (United States)

    2017-03-15

    We identified primary human monocyte-derived macrophages (MDM) as vulnerable target cells for Zika virus (ZIKV) infection. We demonstrate dramatic effects of hemin, the natural inducer of the heme catabolic enzyme heme oxygenase-1 (HO-1), in the reduction of ZIKV replication in vitro. Both LLC-MK2 monkey kidney cells and primary MDM exhibited hemin-induced HO-1 expression with major reductions of >90% in ZIKV replication, with little toxicity to infected cells. Silencing expression of HO-1 or its upstream regulatory gene, nuclear factor erythroid-related factor 2 (Nrf2), attenuated hemin-induced suppression of ZIKV infection, suggesting an important role for induction of these intracellular mediators in retarding ZIKV replication. The inverse correlation between hemin-induced HO-1 levels and ZIKV replication provides a potentially useful therapeutic modality based on stimulation of an innate cellular response against Zika virus infection. - Highlights: •Hemin treatment protected monocyte-derived macrophages against Zika virus (ZIKV) infection. •Innate cellular protection against ZIKV infection correlated with Nrf2-dependent HO-1 expression. •Stimulation of innate cellular responses may provide a therapeutic strategy against ZIKV infection.

  12. Nrf2-dependent induction of innate host defense via heme oxygenase-1 inhibits Zika virus replication

    International Nuclear Information System (INIS)

    Huang, Hanxia; Falgout, Barry; Takeda, Kazuyo; Yamada, Kenneth M.; Dhawan, Subhash

    2017-01-01

    We identified primary human monocyte-derived macrophages (MDM) as vulnerable target cells for Zika virus (ZIKV) infection. We demonstrate dramatic effects of hemin, the natural inducer of the heme catabolic enzyme heme oxygenase-1 (HO-1), in the reduction of ZIKV replication in vitro. Both LLC-MK2 monkey kidney cells and primary MDM exhibited hemin-induced HO-1 expression with major reductions of >90% in ZIKV replication, with little toxicity to infected cells. Silencing expression of HO-1 or its upstream regulatory gene, nuclear factor erythroid-related factor 2 (Nrf2), attenuated hemin-induced suppression of ZIKV infection, suggesting an important role for induction of these intracellular mediators in retarding ZIKV replication. The inverse correlation between hemin-induced HO-1 levels and ZIKV replication provides a potentially useful therapeutic modality based on stimulation of an innate cellular response against Zika virus infection. - Highlights: •Hemin treatment protected monocyte-derived macrophages against Zika virus (ZIKV) infection. •Innate cellular protection against ZIKV infection correlated with Nrf2-dependent HO-1 expression. •Stimulation of innate cellular responses may provide a therapeutic strategy against ZIKV infection.

  13. RAB1A promotes Vaccinia virus replication by facilitating the production of intracellular enveloped virions

    Energy Technology Data Exchange (ETDEWEB)

    Pechenick Jowers, Tali; Featherstone, Rebecca J.; Reynolds, Danielle K.; Brown, Helen K. [The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, Scotland (United Kingdom); James, John; Prescott, Alan [Division of Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland (United Kingdom); Haga, Ismar R. [The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, Scotland (United Kingdom); Beard, Philippa M., E-mail: pip.beard@roslin.ed.ac.uk [The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, Scotland (United Kingdom)

    2015-01-15

    Vaccinia virus (VACV) is a large double-stranded DNA virus with a complex cytoplasmic replication cycle that exploits numerous cellular proteins. This work characterises the role of a proviral cellular protein, the small GTPase RAB1A, in VACV replication. Using siRNA, we identified RAB1A as required for the production of extracellular enveloped virions (EEVs), but not intracellular mature virions (IMVs). Immunofluorescence and electron microscopy further refined the role of RAB1A as facilitating the wrapping of IMVs to become intracellular enveloped virions (IEVs). This is consistent with the known function of RAB1A in maintenance of ER to Golgi transport. VACV can therefore be added to the growing list of viruses which require RAB1A for optimal replication, highlighting this protein as a broadly proviral host factor. - Highlights: • Characterisation of the role of the small GTPase RAB1A in VACV replication. • RAB1A is not required for production of the primary virion form (IMV). • RAB1A is required for production of processed virion forms (IEVs, CEVs and EEVs). • Consistent with known role of RAB1A in ER to Golgi transport.

  14. West Nile virus replication requires fatty acid synthesis but is independent on phosphatidylinositol-4-phosphate lipids.

    Directory of Open Access Journals (Sweden)

    Miguel A Martín-Acebes

    Full Text Available West Nile virus (WNV is a neurovirulent mosquito-borne flavivirus, which main natural hosts are birds but it also infects equines and humans, among other mammals. As in the case of other plus-stranded RNA viruses, WNV replication is associated to intracellular membrane rearrangements. Based on results obtained with a variety of viruses, different cellular processes have been shown to play important roles on these membrane rearrangements for efficient viral replication. As these processes are related to lipid metabolism, fatty acid synthesis, as well as generation of a specific lipid microenvironment enriched in phosphatidylinositol-4-phosphate (PI4P, has been associated to it in other viral models. In this study, intracellular membrane rearrangements following infection with a highly neurovirulent strain of WNV were addressed by means of electron and confocal microscopy. Infection of WNV, and specifically viral RNA replication, were dependent on fatty acid synthesis, as revealed by the inhibitory effect of cerulenin and C75, two pharmacological inhibitors of fatty acid synthase, a key enzyme of this process. However, WNV infection did not induce redistribution of PI4P lipids, and PI4P did not localize at viral replication complex. Even more, WNV multiplication was not inhibited by the use of the phosphatidylinositol-4-kinase inhibitor PIK93, while infection by the enterovirus Coxsackievirus B5 was reduced. Similar features were found when infection by other flavivirus, the Usutu virus (USUV, was analyzed. These features of WNV replication could help to design specific antiviral approaches against WNV and other related flaviviruses.

  15. Replication and shedding kinetics of infectious hematopoietic necrosis virus in juvenile rainbow trout

    Science.gov (United States)

    Wargo, Andrew R.; Scott, Robert J.; Kerr, Benjamin; Kurath, Gael

    2017-01-01

    Viral replication and shedding are key components of transmission and fitness, the kinetics of which are heavily dependent on virus, host, and environmental factors. To date, no studies have quantified the shedding kinetics of infectious hematopoietic necrosis virus (IHNV) in rainbow trout (Oncorhynchus mykiss), or how they are associated with replication, making it difficult to ascertain the transmission dynamics of this pathogen of high agricultural and conservation importance. Here, the replication and shedding kinetics of two M genogroup IHNV genotypes were examined in their naturally co-evolved rainbow trout host. Within host virus replication began rapidly, approaching maximum values by day 3 post-infection, after which viral load was maintained or gradually dropped through day 7. Host innate immune response measured as stimulation of Mx-1 gene expression generally followed within host viral loads. Shedding also began very quickly and peaked within 2 days, defining a generally uniform early peak period of shedding from 1 to 4 days after exposure to virus. This was followed by a post-peak period where shedding declined, such that the majority of fish were no longer shedding by day 12 post-infection. Despite similar kinetics, the average shedding rate over the course of infection was significantly lower in mixed compared to single genotype infections, suggesting a competition effect, however, this did not significantly impact the total amount of virus shed. The data also indicated that the duration of shedding, rather than peak amount of virus shed, was correlated with fish mortality. Generally, the majority of virus produced during infection appeared to be shed into the environment rather than maintained in the host, although there was more retention of within host virus during the post-peak period. Viral virulence was correlated with shedding, such that the more virulent of the two genotypes shed more total virus. This fundamental understanding of IHNV

  16. Molecular genetic analysis of a vaccinia virus gene with an essential role in DNA replication

    International Nuclear Information System (INIS)

    Evans, E.V.A.

    1989-01-01

    The poxvirus, vaccinia, is large DNA virus which replicates in the cytoplasma of the host cell. The virus is believed to encode most or all of the functions required for the temporally regulated transcription and replication of its 186 kilobase genome. Physical and genetic autonomy from the host make vaccinia a useful eukaryotic organism in which to study replication genes and proteins, using a combination of biochemical and genetic techniques. Essential viral functions for replication are identified by conditional lethal mutants that fail to synthesize DNA at the non-permissive temperatures. One such group contains the non-complementing alleles ts17, ts24, ts69 (WR strain). Studies were undertaken to define the phenotype of ts mutants, and to identify and characterize the affected gene and protein. Mutant infection was essentially normal at 32 degree C, but at 39 degree C the mutants did not incorporate 3 H-thymidine into nascent viral DNA or synthesize late viral proteins. If mutant cultures were shifted to non-permissive conditions at the height of replication, DNA synthesis was halted rapidly, implying that the mutants are defective in DNA elongation. The gene affected in the WR mutants and in ts6389, a DNA-minus mutant of the IHD strain, was mapped by marker rescue and corresponds to open reading frame 5 (orfD5) of the viral HindIII D fragment

  17. Peretinoin, an Acyclic Retinoid, Inhibits Hepatitis B Virus Replication by Suppressing Sphingosine Metabolic Pathway In Vitro

    Directory of Open Access Journals (Sweden)

    Kazuhisa Murai

    2018-01-01

    Full Text Available Hepatocellular carcinoma (HCC frequently develops from hepatitis C virus (HCV and hepatitis B virus (HBV infection. We previously reported that peretinoin, an acyclic retinoid, inhibits HCV replication. This study aimed to examine the influence of peretinoin on the HBV lifecycle. HBV-DNA and covalently closed circular DNA (cccDNA were evaluated by a qPCR method in HepG2.2.15 cells. Peretinoin significantly reduced the levels of intracellular HBV-DNA, nuclear cccDNA, and HBV transcript at a concentration that did not induce cytotoxicity. Conversely, other retinoids, such as 9-cis, 13-cis retinoic acid (RA, and all-trans-retinoic acid (ATRA, had no effect or rather increased HBV replication. Mechanistically, although peretinoin increased the expression of HBV-related transcription factors, as observed for other retinoids, peretinoin enhanced the binding of histone deacetylase 1 (HDAC1 to cccDNA in the nucleus and negatively regulated HBV transcription. Moreover, peretinoin significantly inhibited the expression of SPHK1, a potential inhibitor of HDAC activity, and might be involved in hepatic inflammation, fibrosis, and HCC. SPHK1 overexpression in cells cancelled the inhibition of HBV replication induced by peretinoin. This indicates that peretinoin activates HDAC1 and thereby suppresses HBV replication by inhibiting the sphingosine metabolic pathway. Therefore, peretinoin may be a novel therapeutic agent for HBV replication and chemoprevention against HCC.

  18. Morphological and biochemical characterization of the membranous hepatitis C virus replication compartment.

    Science.gov (United States)

    Paul, David; Hoppe, Simone; Saher, Gesine; Krijnse-Locker, Jacomine; Bartenschlager, Ralf

    2013-10-01

    Like all other positive-strand RNA viruses, hepatitis C virus (HCV) induces rearrangements of intracellular membranes that are thought to serve as a scaffold for the assembly of the viral replicase machinery. The most prominent membranous structures present in HCV-infected cells are double-membrane vesicles (DMVs). However, their composition and role in the HCV replication cycle are poorly understood. To gain further insights into the biochemcial properties of HCV-induced membrane alterations, we generated a functional replicon containing a hemagglutinin (HA) affinity tag in nonstructural protein 4B (NS4B), the supposed scaffold protein of the viral replication complex. By using HA-specific affinity purification we isolated NS4B-containing membranes from stable replicon cells. Complementing biochemical and electron microscopy analyses of purified membranes revealed predominantly DMVs, which contained viral proteins NS3 and NS5A as well as enzymatically active viral replicase capable of de novo synthesis of HCV RNA. In addition to viral factors, co-opted cellular proteins, such as vesicle-associated membrane protein-associated protein A (VAP-A) and VAP-B, that are crucial for viral RNA replication, as well as cholesterol, a major structural lipid of detergent-resistant membranes, are highly enriched in DMVs. Here we describe the first isolation and biochemical characterization of HCV-induced DMVs. The results obtained underline their central role in the HCV replication cycle and suggest that DMVs are sites of viral RNA replication. The experimental approach described here is a powerful tool to more precisely define the molecular composition of membranous replication factories induced by other positive-strand RNA viruses, such as picorna-, arteri- and coronaviruses.

  19. Lithium chloride inhibits early stages of foot-and-mouth disease virus (FMDV) replication in vitro.

    Science.gov (United States)

    Zhao, Fu-Rong; Xie, Yin-Li; Liu, Ze-Zhong; Shao, Jun-Jun; Li, Shi-Fang; Zhang, Yong-Guang; Chang, Hui-Yun

    2017-11-01

    Foot-and-mouth disease virus (FMDV) causes an economically important and highly contagious disease of cloven-hoofed animals such as cattle, swine, and sheep. FMD vaccine is the traditional way to protect against the disease, which can greatly reduce its occurrence. However, the use of FMD vaccines to protect early infection is limited. Therefore, the alternative strategy of applying antiviral agents is required to control the spread of FMDV in outbreak situations. As previously reported, LiCl has obviously inhibition effects on a variety of viruses such as transmissible gastroenteritis virus (TGEV), infectious bronchitis coronavirus (IBV), and pseudorabies herpesvirus and EV-A71 virus. In this study, our findings were the first to demonstrate that LiCl inhibition of the FMDV replication. In this study, BHK-21 cell was dose-dependent with LiCl at various stages of FMDV. Virus titration assay was calculated by the 50% tissue culture infected dose (TCID 50 ) with the Reed and Muench method. The cytotoxicity assay of LiCl was performed by the CCK8 kit. The expression level of viral mRNA was measured by RT-qPCR. The results revealed LiCl can inhibit FMDV replication, but it cannot affect FMDV attachment stage and entry stage in the course of FMDV life cycle. Further studies confirmed that the LiCl affect the replication stage of FMDV, especially the early stages of FMDV replication. So LiCl has potential as an effective anti-FMDV drug. Therefore, LiCl may be an effective drug for the control of FMDV. Based on that, the mechanism of the antiviral effect of LiCl on FMDV infection is need to in-depth research in vivo. © 2017 Wiley Periodicals, Inc.

  20. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes

    International Nuclear Information System (INIS)

    Sanada, Takahiro; Tsukiyama-Kohara, Kyoko; Yamamoto, Naoki; Ezzikouri, Sayeh; Benjelloun, Soumaya; Murakami, Shuko; Tanaka, Yasuhito; Tateno, Chise; Kohara, Michinori

    2016-01-01

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3–6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10"5 copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10"4-10"6 copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10"3 copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. - Highlights: • Primary hepatocytes were established from tupaia that is a novel HBV infection model. • Tupaia primary hepatocytes were susceptible for HBV infection. • The immunodeficient chimeric mice with tupaia hepatocytes were established. • The chimeric mice with tupaia hepatocytes were susceptible for HBV infection.

  1. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes.

    Science.gov (United States)

    Sanada, Takahiro; Tsukiyama-Kohara, Kyoko; Yamamoto, Naoki; Ezzikouri, Sayeh; Benjelloun, Soumaya; Murakami, Shuko; Tanaka, Yasuhito; Tateno, Chise; Kohara, Michinori

    2016-01-08

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3-6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10(5) copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10(4)-10(6) copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10(3) copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sanada, Takahiro [Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506 (Japan); Tsukiyama-Kohara, Kyoko, E-mail: kkohara@vet.kagoshima-u.ac.jp [Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24, Korimoto, Kagoshima-city, Kagoshima 890-0065 (Japan); Laboratory of Animal Hygiene, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24, Korimoto, Kagoshima, Kagoshima 890-0065 (Japan); Yamamoto, Naoki [Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506 (Japan); Ezzikouri, Sayeh; Benjelloun, Soumaya [Viral Hepatitis Laboratory, Virology Unit, Institut Pasteur du Maroc, 1, Louis Pasteur, Casablanca 20360 (Morocco); Murakami, Shuko; Tanaka, Yasuhito [Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Sciences, Kawasumi 1, Mizuho-ku, Nagoya, Aichi 467-8601 (Japan); Tateno, Chise [PhoenixBio Co. Ltd., 3-4-1, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046 (Japan); Kohara, Michinori, E-mail: kohara-mc@igakuken.or.jp [Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506 (Japan)

    2016-01-08

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3–6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10{sup 5} copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10{sup 4}-10{sup 6} copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10{sup 3} copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. - Highlights: • Primary hepatocytes were established from tupaia that is a novel HBV infection model. • Tupaia primary hepatocytes were susceptible for HBV infection. • The immunodeficient chimeric mice with tupaia hepatocytes were established. • The chimeric mice with tupaia hepatocytes were susceptible for HBV infection.

  3. Conserved elements within the genome of foot-and mouth disease virus; their influence on virus replication

    DEFF Research Database (Denmark)

    Kjær, Jonas; Poulsen, Line D.; Vinther, Jeppe

    Objectives: Several conserved elements within the genome of foot-and-mouth disease virus (FMDV) have been identified, e.g. the IRES. Such elements can be crucial for the efficient replication of the genomic RNA. Previously, SHAPE analysis of the entire FMDV genome (Poulsen et al., 2016 submitted......) has identified a conserved RNA structure within the 3Dpol coding region (the RNA-dependent RNA polymerase) which might have an important role in virus replication. The FMDV 2A peptide, another conserved element, is responsible for the primary “cleavage” at its own C-terminus (2A/2B junction......). It is believed that this “cleavage” is achieved by ribosomal skipping, in which the 2A peptide prevents the ribosome from linking the next amino acid (aa) to the growing polypeptide. The nature of this “cleavage” has so far not been investigated in the context of the full-length FMDV RNA within cells. Through...

  4. Characteristics and Their Clinical Relevance of Respiratory Syncytial Virus Types and Genotypes Circulating in Northern Italy in Five Consecutive Winter Seasons.

    Directory of Open Access Journals (Sweden)

    Susanna Esposito

    Full Text Available In order to investigate the genetic diversity and patterns of the co-circulating genotypes of respiratory syncytial virus (RSV and their possible relationships with the severity of RSV infection, we studied all of the RSV-positive nasopharyngeal samples collected from children during five consecutive winters (2009-2010, 2010-2011, 2011-2012, 2012-2013 and 2013-2014. The RSVs were detected using the respiratory virus panel fast assay and single-tube RT-PCR, their nucleotides were sequenced, and they were tested for positive selection. Of the 165 positive samples, 131 (79.4% carried RSV-A and 34 (20.6% RSV-B; both groups co-circulated in all of the study periods, with RSV-A predominating in all the seasons except for winter 2010-2011, which had a predominance of RSV-B. Phylogenetic analysis of the RSV-A sequences identified genotypes NA1 and ON1, the second replacing the first during the last two years of the study period. The RSV-B belonged to genotypes BA9 and BA10. BA9 was detected in all the years of the study whereas BA only desultorily. Comparison of the subjects infected by RSV-A and RSV-B types did not reveal any significant differences, but the children infected by genotype A/NA1 more frequently had lower respiratory tract infections (p<0.0001 and required hospitalisation (p = 0.007 more often than those infected by genotype A/ON1. These findings show that RSV has complex patterns of circulation characterised by the periodical replacement of the predominant genotypes, and indicate that the circulation and pathogenic role of the different RSV strains should be investigated as each may have a different impact on the host. A knowledge of the correlations between types, genotypes and disease severity may also be important in order to be able to include the more virulent strains in future vaccines.

  5. A Novel System for Identification of Inhibitors of Rift Valley Fever Virus Replication

    Directory of Open Access Journals (Sweden)

    Mary E. Piper

    2010-03-01

    Full Text Available Rift Valley fever virus (RVFV is a human and livestock pathogen endemic to sub-Saharan Africa. We have developed a T7-dependent system for the efficient production of RVFV-like particles (RVF-VLPs based on the virulent ZH-501 strain of RVFV. The RVF-VLPs are capable of performing a single round of infection, allowing for the study of viral replication, assembly, and infectivity. We demonstrate that these RVF-VLPs are antigenically indistinguishable from authentic RVFV and respond similarly to a wide array of known and previously unknown chemical inhibitors. This system should be useful for screening for small molecule inhibitors of RVFV replication.

  6. A novel system for identification of inhibitors of rift valley Fever virus replication.

    Science.gov (United States)

    Piper, Mary E; Gerrard, Sonja R

    2010-03-01

    Rift Valley fever virus (RVFV) is a human and livestock pathogen endemic to sub-Saharan Africa. We have developed a T7-dependent system for the efficient production of RVFV-like particles (RVF-VLPs) based on the virulent ZH-501 strain of RVFV. The RVF-VLPs are capable of performing a single round of infection, allowing for the study of viral replication, assembly, and infectivity. We demonstrate that these RVF-VLPs are antigenically indistinguishable from authentic RVFV and respond similarly to a wide array of known and previously unknown chemical inhibitors. This system should be useful for screening for small molecule inhibitors of RVFV replication.

  7. Differential impact of respiratory syncytial virus and parainfluenza virus on the frequency of acute otitis media is explained by lower adaptive and innate immune responses in otitis-prone children.

    Science.gov (United States)

    Verhoeven, David; Xu, Qingfu; Pichichero, Michael E

    2014-08-01

    Acute otitis media (AOM) is a leading cause of bacterial pediatric infections associated with viral upper respiratory infections (URIs). We examined the differential impact of respiratory syncytial virus (RSV) and parainfluenza virus URIs on the frequency of AOM caused by Streptococcus pneumoniae (Spn) and nontypeable Haemophilus influenzae (NTHi) in stringently defined otitis-prone (sOP) and non-otitis-prone (NOP) children as a potential mechanism to explain increased susceptibility to AOM. Peripheral blood and nasal washes were obtained from sOP and NOP children (n = 309). Colonization events and antiviral responses consisting of total specific immunoglobulin G (IgG) responses, neutralizing antibody responses, and T-cell responses were determined. Isolated neutrophils were infected with varying multiplicities of infection of both viruses, and opsonophagocytosis potential was measured. A significant increase was found in frequency of AOM events caused by Spn and NTHi, with a concurrent RSV infection in sOP children. These results correlated with diminished total RSV-specific IgG, higher viral nasal burdens, and lower IgG neutralizing capacity. The sOP children had diminished T-cell responses to RSV that correlated with lower Toll-like receptor 3/7 transcript and decreased expression of HLA-DR on antigen-presenting cells. RSV interfered with the Spn phagocytic capacity of neutrophils in a dose-dependent manner. Parainfluenza virus infections did not differentially affect AOM events in sOP and NOP children. Lower innate and adaptive immune responses to RSV in sOP children may slow the kinetics of viral clearance from the nasopharynx and allow for viral interference with antibacterial immune responses, thus contributing to increased frequency of AOMs. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  8. Isolation and characterization of highly replicable hepatitis C virus genotype 1a strain HCV-RMT.

    Science.gov (United States)

    Arai, Masaaki; Tokunaga, Yuko; Takagi, Asako; Tobita, Yoshimi; Hirata, Yuichi; Ishida, Yuji; Tateno, Chise; Kohara, Michinori

    2013-01-01

    Multiple genotype 1a clones have been reported, including the very first hepatitis C virus (HCV) clone called H77. The replication ability of some of these clones has been confirmed in vitro and in vivo, although this ability is somehow compromised. We now report a newly isolated genotype 1a clone, designated HCV-RMT, which has the ability to replicate efficiently in patients, chimeric mice with humanized liver, and cultured cells. An authentic subgenomic replicon cell line was established from the HCV-RMT sequence with spontaneous introduction of three adaptive mutations, which were later confirmed to be responsible for efficient replication in HuH-7 cells as both subgenomic replicon RNA and viral genome RNA. Following transfection, the HCV-RMT RNA genome with three adaptive mutations was maintained for more than 2 months in HuH-7 cells. One clone selected from the transfected cells had a high copy number, and its supernatant could infect naïve HuH-7 cells. Direct injection of wild-type HCV-RMT RNA into the liver of chimeric mice with humanized liver resulted in vigorous replication, similar to inoculation with the parental patient's serum. A study of virus replication using HCV-RMT derivatives with various combinations of adaptive mutations revealed a clear inversely proportional relationship between in vitro and in vivo replication abilities. Thus, we suggest that HCV-RMT and its derivatives are important tools for HCV genotype 1a research and for determining the mechanism of HCV replication in vitro and in vivo.

  9. Isolation and characterization of highly replicable hepatitis C virus genotype 1a strain HCV-RMT.

    Directory of Open Access Journals (Sweden)

    Masaaki Arai

    Full Text Available Multiple genotype 1a clones have been reported, including the very first hepatitis C virus (HCV clone called H77. The replication ability of some of these clones has been confirmed in vitro and in vivo, although this ability is somehow compromised. We now report a newly isolated genotype 1a clone, designated HCV-RMT, which has the ability to replicate efficiently in patients, chimeric mice with humanized liver, and cultured cells. An authentic subgenomic replicon cell line was established from the HCV-RMT sequence with spontaneous introduction of three adaptive mutations, which were later confirmed to be responsible for efficient replication in HuH-7 cells as both subgenomic replicon RNA and viral genome RNA. Following transfection, the HCV-RMT RNA genome with three adaptive mutations was maintained for more than 2 months in HuH-7 cells. One clone selected from the transfected cells had a high copy number, and its supernatant could infect naïve HuH-7 cells. Direct injection of wild-type HCV-RMT RNA into the liver of chimeric mice with humanized liver resulted in vigorous replication, similar to inoculation with the parental patient's serum. A study of virus replication using HCV-RMT derivatives with various combinations of adaptive mutations revealed a clear inversely proportional relationship between in vitro and in vivo replication abilities. Thus, we suggest that HCV-RMT and its derivatives are important tools for HCV genotype 1a research and for determining the mechanism of HCV replication in vitro and in vivo.

  10. Differential replication of Foot-and-mouth disease viruses in mice determine lethality.

    Science.gov (United States)

    Cacciabue, Marco; García-Núñez, María Soledad; Delgado, Fernando; Currá, Anabella; Marrero, Rubén; Molinari, Paula; Rieder, Elizabeth; Carrillo, Elisa; Gismondi, María Inés

    2017-09-01

    Adult C57BL/6J mice have been used to study Foot-and-mouth disease virus (FMDV) biology. In this work, two variants of an FMDV A/Arg/01 strain exhibiting differential pathogenicity in adult mice were identified and characterized: a non-lethal virus (A01NL) caused mild signs of disease, whereas a lethal virus (A01L) caused death within 24-48h independently of the dose used. Both viruses caused a systemic infection with pathological changes in the exocrine pancreas. Virus A01L reached higher viral loads in plasma and organs of inoculated mice as well as increased replication in an ovine kidney cell line. Complete consensus sequences revealed 6 non-synonymous changes between A01L and A10NL genomes that might be linked to replication differences, as suggested by in silico prediction studies. Our results highlight the biological significance of discrete genomic variations and reinforce the usefulness of this animal model to study viral determinants of lethality. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Tombusviruses upregulate phospholipid biosynthesis via interaction between p33 replication protein and yeast lipid sensor proteins during virus replication in yeast

    International Nuclear Information System (INIS)

    Barajas, Daniel; Xu, Kai; Sharma, Monika; Wu, Cheng-Yu; Nagy, Peter D.

    2014-01-01

    Positive-stranded RNA viruses induce new membranous structures and promote membrane proliferation in infected cells to facilitate viral replication. In this paper, the authors show that a plant-infecting tombusvirus upregulates transcription of phospholipid biosynthesis genes, such as INO1, OPI3 and CHO1, and increases phospholipid levels in yeast model host. This is accomplished by the viral p33 replication protein, which interacts with Opi1p FFAT domain protein and Scs2p VAP protein. Opi1p and Scs2p are phospholipid sensor proteins and they repress the expression of phospholipid genes. Accordingly, deletion of OPI1 transcription repressor in yeast has a stimulatory effect on TBSV RNA accumulation and enhanced tombusvirus replicase activity in an in vitro assay. Altogether, the presented data convincingly demonstrate that de novo lipid biosynthesis is required for optimal TBSV replication. Overall, this work reveals that a (+)RNA virus reprograms the phospholipid biosynthesis pathway in a unique way to facilitate its replication in yeast cells. - Highlights: • Tombusvirus p33 replication protein interacts with FFAT-domain host protein. • Tombusvirus replication leads to upregulation of phospholipids. • Tombusvirus replication depends on de novo lipid synthesis. • Deletion of FFAT-domain host protein enhances TBSV replication. • TBSV rewires host phospholipid synthesis

  12. Intermolecular RNA Recombination Occurs at Different Frequencies in Alternate Forms of Brome Mosaic Virus RNA Replication Compartments

    Directory of Open Access Journals (Sweden)

    Hernan Garcia-Ruiz

    2018-03-01

    Full Text Available Positive-strand RNA viruses replicate their genomes in membrane-bound replication compartments. Brome mosaic virus (BMV replicates in vesicular invaginations of the endoplasmic reticulum membrane. BMV has served as a productive model system to study processes like virus-host interactions, RNA replication and recombination. Here we present multiple lines of evidence showing that the structure of the viral RNA replication compartments plays a fundamental role and that recruitment of parental RNAs to a common replication compartment is a limiting step in intermolecular RNA recombination. We show that a previously defined requirement for an RNA recruitment element on both parental RNAs is not to function as a preferred crossover site, but in order for individual RNAs to be recruited into the replication compartments. Moreover, modulating the form of the replication compartments from spherular vesicles (spherules to more expansive membrane layers increased intermolecular RNA recombination frequency by 200- to 1000-fold. We propose that intermolecular RNA recombination requires parental RNAs to be recruited into replication compartments as monomers, and that recruitment of multiple RNAs into a contiguous space is much more common for layers than for spherules. These results could explain differences in recombination frequencies between viruses that replicate in association with smaller spherules versus larger double-membrane vesicles and convoluted membranes.

  13. The logic of DNA replication in double-stranded DNA viruses: insights from global analysis of viral genomes.

    Science.gov (United States)

    Kazlauskas, Darius; Krupovic, Mart; Venclovas, Česlovas

    2016-06-02

    Genomic DNA replication is a complex process that involves multiple proteins. Cellular DNA replication systems are broadly classified into only two types, bacterial and archaeo-eukaryotic. In contrast, double-stranded (ds) DNA viruses feature a much broader diversity of DNA replication machineries. Viruses differ greatly in both completeness and composition of their sets of DNA replication proteins. In this study, we explored whether there are common patterns underlying this extreme diversity. We identified and analyzed all major functional groups of DNA replication proteins in all available proteomes of dsDNA viruses. Our results show that some proteins are common to viruses infecting all domains of life and likely represent components of the ancestral core set. These include B-family polymerases, SF3 helicases, archaeo-eukaryotic primases, clamps and clamp loaders of the archaeo-eukaryotic type, RNase H and ATP-dependent DNA ligases. We also discovered a clear correlation between genome size and self-sufficiency of viral DNA replication, the unanticipated dominance of replicative helicases and pervasive functional associations among certain groups of DNA replication proteins. Altogether, our results provide a comprehensive view on the diversity and evolution of replication systems in the DNA virome and uncover fundamental principles underlying the orchestration of viral DNA replication. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  14. Visualization and measurement of ATP levels in living cells replicating hepatitis C virus genome RNA.

    Directory of Open Access Journals (Sweden)

    Tomomi Ando

    Full Text Available Adenosine 5'-triphosphate (ATP is the primary energy currency of all living organisms and participates in a variety of cellular processes. Although ATP requirements during viral lifecycles have been examined in a number of studies, a method by which ATP production can be monitored in real-time, and by which ATP can be quantified in individual cells and subcellular compartments, is lacking, thereby hindering studies aimed at elucidating the precise mechanisms by which viral replication energized by ATP is controlled. In this study, we investigated the fluctuation and distribution of ATP in cells during RNA replication of the hepatitis C virus (HCV, a member of the Flaviviridae family. We demonstrated that cells involved in viral RNA replication actively consumed ATP, thereby reducing cytoplasmic ATP levels. Subsequently, a method to measure ATP levels at putative subcellular sites of HCV RNA replication in living cells was developed by introducing a recently-established Förster resonance energy transfer (FRET-based ATP indicator, called ATeam, into the NS5A coding region of the HCV replicon. Using this method, we were able to observe the formation of ATP-enriched dot-like structures, which co-localize with non-structural viral proteins, within the cytoplasm of HCV-replicating cells but not in non-replicating cells. The obtained FRET signals allowed us to estimate ATP concentrations within HCV replicating cells as ∼5 mM at possible replicating sites and ∼1 mM at peripheral sites that did not appear to be involved in HCV replication. In contrast, cytoplasmic ATP levels in non-replicating Huh-7 cells were estimated as ∼2 mM. To our knowledge, this is the first study to demonstrate changes in ATP concentration within cells during replication of the HCV genome and increased ATP levels at distinct sites within replicating cells. ATeam may be a powerful tool for the study of energy metabolism during replication of the viral genome.

  15. Luteolin restricts dengue virus replication through inhibition of the proprotein convertase furin.

    Science.gov (United States)

    Peng, Minhua; Watanabe, Satoru; Chan, Kitti Wing Ki; He, Qiuyan; Zhao, Ya; Zhang, Zhongde; Lai, Xiaoping; Luo, Dahai; Vasudevan, Subhash G; Li, Geng

    2017-07-01

    In many countries afflicted with dengue fever, traditional medicines are widely used as panaceas for illness, and here we describe the systematic evaluation of a widely known natural product, luteolin, originating from the "heat clearing" class of herbs. We show that luteolin inhibits the replication of all four serotypes of dengue virus, but the selectivity of the inhibition was weak. In addition, ADE-mediated dengue virus infection of human cell lines and primary PBMCs was inhibited. In a time-of-drug-addition study, luteolin was found to reduce infectious virus particle formation, but not viral RNA synthesis, in Huh-7 cells. During the virus life cycle, the host protease furin cleaves the pr moiety from prM protein of immature virus particles in the trans-Golgi network to produce mature virions. Analysis of virus particles from luteolin-treated cells revealed that prM was not cleaved efficiently. Biochemical interrogation of human furin showed that luteolin inhibited the enzyme activity in an uncompetitive manner, with Ki value of 58.6 μM, suggesting that treatment may restrict the virion maturation process. Luteolin also exhibited in vivo antiviral activity in mice infected with DENV, causing reduced viremia. Given the mode of action of luteolin and its widespread source, it is possible that it can be tested in combination with other dengue virus inhibitors. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. In Vivo Regulation of Hepatitis B Virus Replication by Peroxisome Proliferators†

    Science.gov (United States)

    Guidotti, Luca G.; Eggers, Carrie M.; Raney, Anneke K.; Chi, Susan Y.; Peters, Jeffrey M.; Gonzalez, Frank J.; McLachlan, Alan

    1999-01-01

    The role of the peroxisome proliferator-activated receptor α (PPARα) in regulating hepatitis B virus (HBV) transcription and replication in vivo was investigated in an HBV transgenic mouse model. Treatment of HBV transgenic mice with the peroxisome proliferators Wy-14,643 and clofibric acid resulted in a less than twofold increase in HBV transcription rates and steady-state levels of HBV RNAs in the livers of these mice. In male mice, this increase in transcription was associated with a 2- to 3-fold increase in replication intermediates, whereas in female mice it was associated with a 7- to 14-fold increase in replication intermediates. The observed increases in transcription and replication were dependent on PPARα. HBV transgenic mice lacking this nuclear hormone receptor showed similar levels of HBV transcripts and replication intermediates as untreated HBV transgenic mice expressing PPARα but failed to demonstrate alterations in either RNA or DNA synthesis in response to peroxisome proliferators. Therefore, it appears that very modest alterations in transcription can, under certain circumstances, result in relatively large increases in HBV replication in HBV transgenic mice. PMID:10559356

  17. Nordihydroguaiaretic acid (NDGA) inhibits replication and viral morphogenesis of dengue virus.

    Science.gov (United States)

    Soto-Acosta, Rubén; Bautista-Carbajal, Patricia; Syed, Gulam H; Siddiqui, Aleem; Del Angel, Rosa M

    2014-09-01

    Dengue is the most common mosquito borne viral disease in humans. The infection with any of the 4 dengue virus serotypes (DENV) can either be asymptomatic or manifest in two clinical forms, the mild dengue fever or the more severe dengue hemorrhagic fever that may progress into dengue shock syndrome. A DENV replicative cycle relies on host lipid metabolism; specifically, DENV infection modulates cholesterol and fatty acid synthesis, generating a lipid-enriched cellular environment necessary for viral replication. Thus, the aim of this work was to evaluate the anti-DENV effect of the Nordihydroguaiaretic acid (NDGA), a hypolipidemic agent with antioxidant and anti-inflammatory properties. A dose-dependent inhibition in viral yield and NS1 secretion was observed in supernatants of infected cells treated for 24 and 48 h with different concentrations of NDGA. To evaluate the effect of NDGA in DENV replication, a DENV4 replicon transfected Vero cells were treated with different concentrations of NDGA. NDGA treatment significantly reduced DENV replication, reiterating the importance of lipids in viral replication. NDGA treatment also led to reduction in number of lipid droplets (LDs), the neutral lipid storage organelles involved in DENV morphogenesis that are known to increase in number during DENV infection. Furthermore, NDGA treatment resulted in dissociation of the C protein from LDs. Overall our results suggest that NDGA inhibits DENV infection by targeting genome replication and viral assembly. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Histone Deacetylase 1 Plays an Acetylation-Independent Role in Influenza A Virus Replication

    Directory of Open Access Journals (Sweden)

    Lin Chen

    2017-12-01

    Full Text Available Influenza A viruses (IAVs take advantage of the host acetylation system for their own benefit. Whether the nucleoprotein (NP of IAVs undergoes acetylation and the interaction between the NP and the class I histone deacetylases (HDACs were largely unknown. Here, we showed that the NP protein of IAV interacted with HDAC1, which downregulated the acetylation level of NP. Using mass spectrometry, we identified lysine 103 as an acetylation site of the NP. Compared with wild-type protein, two K103 NP mutants, K103A and K103R, enhanced replication efficiency of the recombinant viruses in vitro. We further demonstrated that HDAC1 facilitated viral replication via two paths: promoting the nuclear retention of NP and inhibiting TBK1-IRF3 pathway. Our results lead to a new mechanism for regulating NP acetylation, indicating that HDAC1 may be a possible target for antiviral drugs.

  19. Autophagy sustains the replication of porcine reproductive and respiratory virus in host cells

    International Nuclear Information System (INIS)

    Liu, Qinghao; Qin, Yixian; Zhou, Lei; Kou, Qiuwen; Guo, Xin; Ge, Xinna; Yang, Hanchun; Hu, Hongbo

    2012-01-01

    In this study, we confirmed the autophagy induced by porcine reproductive and respiratory syndrome virus (PRRSV) in permissive cells and investigated the role of autophagy in the replication of PRRSV. We first demonstrated that PRRSV infection significantly results in the increased double-membrane vesicles, the accumulation of LC3 fluorescence puncta, and the raised ratio of LC3-II/β-actin, in MARC-145 cells. Then we discovered that induction of autophagy by rapamycin significantly enhances the viral titers of PRRSV, while inhibition of autophagy by 3-MA and silencing of LC3 gene by siRNA reduces the yield of PRRSV. The results showed functional autolysosomes can be formed after PRRSV infection and the autophagosome–lysosome-fusion inhibitor decreases the virus titers. We also examined the induction of autophagy by PRRSV infection in pulmonary alveolar macrophages. These findings indicate that autophagy induced by PRRSV infection plays a role in sustaining the replication of PRRSV in host cells.

  20. Autophagy sustains the replication of porcine reproductive and respiratory virus in host cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qinghao; Qin, Yixian; Zhou, Lei; Kou, Qiuwen; Guo, Xin; Ge, Xinna [Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agribiotechnology, China Agricultural University, Beijing (China); Yang, Hanchun, E-mail: yanghanchun1@cau.edu.cn [Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agribiotechnology, China Agricultural University, Beijing (China); Hu, Hongbo, E-mail: hongbo@cau.edu.cn [College of Food Science and Nutritional Engineering, China Agricultural University, Beijing (China)

    2012-08-01

    In this study, we confirmed the autophagy induced by porcine reproductive and respiratory syndrome virus (PRRSV) in permissive cells and investigated the role of autophagy in the replication of PRRSV. We first demonstrated that PRRSV infection significantly results in the increased double-membrane vesicles, the accumulation of LC3 fluorescence puncta, and the raised ratio of LC3-II/{beta}-actin, in MARC-145 cells. Then we discovered that induction of autophagy by rapamycin significantly enhances the viral titers of PRRSV, while inhibition of autophagy by 3-MA and silencing of LC3 gene by siRNA reduces the yield of PRRSV. The results showed functional autolysosomes can be formed after PRRSV infection and the autophagosome-lysosome-fusion inhibitor decreases the virus titers. We also examined the induction of autophagy by PRRSV infection in pulmonary alveolar macrophages. These findings indicate that autophagy induced by PRRSV infection plays a role in sustaining the replication of PRRSV in host cells.

  1. Rapid Titration of Measles and Other Viruses: Optimization with Determination of Replication Cycle Length

    Science.gov (United States)

    Grigorov, Boyan; Rabilloud, Jessica; Lawrence, Philip; Gerlier, Denis

    2011-01-01

    Background Measles virus (MV) is a member of the Paramyxoviridae family and an important human pathogen causing strong immunosuppression in affected individuals and a considerable number of deaths worldwide. Currently, measles is a re-emerging disease in developed countries. MV is usually quantified in infectious units as determined by limiting dilution and counting of plaque forming unit either directly (PFU method) or indirectly from random distribution in microwells (TCID50 method). Both methods are time-consuming (up to several days), cumbersome and, in the case of the PFU assay, possibly operator dependent. Methods/Findings A rapid, optimized, accurate, and reliable technique for titration of measles virus was developed based on the detection of virus infected cells by flow cytometry, single round of infection and titer calculation according to the Poisson's law. The kinetics follow up of the number of infected cells after infection with serial dilutions of a virus allowed estimation of the duration of the replication cycle, and consequently, the optimal infection time. The assay was set up to quantify measles virus, vesicular stomatitis virus (VSV), and human immunodeficiency virus type 1 (HIV-1) using antibody labeling of viral glycoprotein, virus encoded fluorescent reporter protein and an inducible fluorescent-reporter cell line, respectively. Conclusion Overall, performing the assay takes only 24–30 hours for MV strains, 12 hours for VSV, and 52 hours for HIV-1. The step-by-step procedure we have set up can be, in principle, applicable to accurately quantify any virus including lentiviral vectors, provided that a virus encoded gene product can be detected by flow cytometry. PMID:21915289

  2. Differential virulence mechanisms of infectious hematopoietic necrosis virus in rainbow trout (Oncorhynchus mykiss) include host entry and virus replication kinetics

    Science.gov (United States)

    Penaranda, M.M.D.; Purcell, M.K.; Kurath, G.

    2009-01-01

    Host specificity is a phenomenon exhibited by all viruses. For the fish rhabdovirus infectious hematopoietic necrosis virus (IHNV), differential specificity of virus strains from the U and M genogroups has been established both in the field and in experimental challenges. In rainbow trout (Oncorhynchus mykiss), M IHNV strains are consistently more prevalent and more virulent than U IHNV. The basis of the differential ability of these two IHNV genogroups to cause disease in rainbow trout was investigated in live infection challenges with representative U and M IHNV strains. When IHNV was delivered by intraperitoneal injection, the mortality caused by U IHNV increased, indicating that the low virulence of U IHNV is partly due to inefficiency in entering the trout host. Analyses of in vivo replication showed that U IHNV consistently had lower prevalence and lower viral load than M IHNV during the course of infection. In analyses of the host immune response, M IHNV-infected fish consistently had higher and longer expression of innate immune-related genes such as Mx-1. This suggests that the higher virulence of M IHNV is not due to suppression of the immune response in rainbow trout. Taken together, the results support a kinetics hypothesis wherein faster replication enables M IHNV to rapidly achieve a threshold level of virus necessary to override the strong host innate immune response. ?? 2009 SGM.

  3. Signals Involved in Regulation of Hepatitis C Virus RNA Genome Translation and Replication

    Directory of Open Access Journals (Sweden)

    Michael Niepmann

    2018-03-01

    Full Text Available Hepatitis C virus (HCV preferentially replicates in the human liver and frequently causes chronic infection, often leading to cirrhosis and liver cancer. HCV is an enveloped virus classified in the genus Hepacivirus in the family Flaviviridae and has a single-stranded RNA genome of positive orientation. The HCV RNA genome is translated and replicated in the cytoplasm. Translation is controlled by the Internal Ribosome Entry Site (IRES in the 5′ untranslated region (5′ UTR, while also downstream elements like the cis-replication element (CRE in the coding region and the 3′ UTR are involved in translation regulation. The cis-elements controlling replication of the viral RNA genome are located mainly in the 5′- and 3′-UTRs at the genome ends but also in the protein coding region, and in part these signals overlap with the signals controlling RNA translation. Many long-range RNA–RNA interactions (LRIs are predicted between different regions of the HCV RNA genome, and several such LRIs are actually involved in HCV translation and replication regulation. A number of RNA cis-elements recruit cellular RNA-binding proteins that are involved in the regulation of HCV translation and replication. In addition, the liver-specific microRNA-122 (miR-122 binds to two target sites at the 5′ end of the viral RNA genome as well as to at least three additional target sites in the coding region and the 3′ UTR. It is involved in the regulation of HCV RNA stability, translation and replication, thereby largely contributing to the hepatotropism of HCV. However, we are still far from completely understanding all interactions that regulate HCV RNA genome translation, stability, replication and encapsidation. In particular, many conclusions on the function of cis-elements in HCV replication have been obtained using full-length HCV genomes or near-full-length replicon systems. These include both genome ends, making it difficult to decide if a cis-element in

  4. Signals Involved in Regulation of Hepatitis C Virus RNA Genome Translation and Replication.

    Science.gov (United States)

    Niepmann, Michael; Shalamova, Lyudmila A; Gerresheim, Gesche K; Rossbach, Oliver

    2018-01-01

    Hepatitis C virus (HCV) preferentially replicates in the human liver and frequently causes chronic infection, often leading to cirrhosis and liver cancer. HCV is an enveloped virus classified in the genus Hepacivirus in the family Flaviviridae and has a single-stranded RNA genome of positive orientation. The HCV RNA genome is translated and replicated in the cytoplasm. Translation is controlled by the Internal Ribosome Entry Site (IRES) in the 5' untranslated region (5' UTR), while also downstream elements like the cis -replication element (CRE) in the coding region and the 3' UTR are involved in translation regulation. The cis -elements controlling replication of the viral RNA genome are located mainly in the 5'- and 3'-UTRs at the genome ends but also in the protein coding region, and in part these signals overlap with the signals controlling RNA translation. Many long-range RNA-RNA interactions (LRIs) are predicted between different regions of the HCV RNA genome, and several such LRIs are actually involved in HCV translation and replication regulation. A number of RNA cis -elements recruit cellular RNA-binding proteins that are involved in the regulation of HCV translation and replication. In addition, the liver-specific microRNA-122 (miR-122) binds to two target sites at the 5' end of the viral RNA genome as well as to at least three additional target sites in the coding region and the 3' UTR. It is involved in the regulation of HCV RNA stability, translation and replication, thereby largely contributing to the hepatotropism of HCV. However, we are still far from completely understanding all interactions that regulate HCV RNA genome translation, stability, replication and encapsidation. In particular, many conclusions on the function of cis -elements in HCV replication have been obtained using full-length HCV genomes or near-full-length replicon systems. These include both genome ends, making it difficult to decide if a cis -element in question acts on HCV

  5. Frog virus 3 ORF 53R, a putative myristoylated membrane protein, is essential for virus replication in vitro

    International Nuclear Information System (INIS)

    Whitley, Dexter S.; Yu, Kwang; Sample, Robert C.; Sinning, Allan; Henegar, Jeffrey; Norcross, Erin; Chinchar, V. Gregory

    2010-01-01

    Although previous work identified 12 complementation groups with possible roles in virus assembly, currently only one frog virus 3 protein, the major capsid protein (MCP), has been linked with virion formation. To identify other proteins required for assembly, we used an antisense morpholino oligonucleotide to target 53R, a putative myristoylated membrane protein, and showed that treatment resulted in marked reductions in 53R levels and a 60% drop in virus titers. Immunofluorescence assays confirmed knock down and showed that 53R was found primarily within viral assembly sites, whereas transmission electron microscopy detected fewer mature virions and, in some cells, dense granular bodies that may represent unencapsidated DNA-protein complexes. Treatment with a myristoylation inhibitor (2-hydroxymyristic acid) resulted in an 80% reduction in viral titers. Collectively, these data indicate that 53R is an essential viral protein that is required for replication in vitro and suggest it plays a critical role in virion formation.

  6. Visualization of the structures of the hepatitis C virus replication complex

    International Nuclear Information System (INIS)

    Chan, Shih-Ching; Lo, Shih-Yen; Liou, Je-Wen; Lin, Min-Ching; Syu, Ciao-Ling; Lai, Meng-Jiun; Chen, Yi- Cheng; Li, Hui-Chun

    2011-01-01

    Research highlights: → Lipid rafts are known to play an important role in virus entry and virus assembly of many viruses. → However, HCV is the first example of the association of lipid raft with viral RNA replication. → Our results in this manuscript demonstrate that purified HCV RCs with associated lipid raft membrane appeared as distinct particles of around 0.7 um under EM and AFM. → Knockdown of proteins associated with lipid raft suppressed the HCV replication and reduced the number of these particles. → To our knowledge, structures of HCV RCs were demonstrated at its first time in this manuscript. -- Abstract: Hepatitis C viral RNA synthesis has been demonstrated to occur on a lipid raft membrane structure. Lipid raft membrane fraction purified by membrane flotation analysis was observed using transmission electron microscopy and atomic force microscopy. Particles around 0.7 um in size were found in lipid raft membrane fraction purified from hepatitis C virus (HCV) replicon but not their parental HuH7 cells. HCV NS5A protein was associated with these specialized particles. After several cycles of freezing-thawing, these particles would fuse into larger sizes up to 10 um. Knockdown of seven proteins associated with lipid raft (VAPA, COPG, RAB18, COMT, CDC42, DPP4, and KDELR2) of HCV replicon cells reduced the observed number of these particles and suppressed the HCV replication. Results in this study indicated that HCV replication complexes with associated lipid raft membrane form distinct particle structures of around 0.7 um as observed from transmission electron microscopy and atomic force microscopy.

  7. Genome of the Acidianus bottle-shaped virus and insights into the replication and packaging mechanisms

    DEFF Research Database (Denmark)

    Peng, Xu; Basta, Tamara; Häring, Monika

    2007-01-01

    of the bacteriophage varphi29 and the human adenovirus. The region contains the genes for a putative protein-primed DNA polymerase, and a small putative RNA with a predicted secondary structure closely similar to that of the prohead RNA of bacteriophage varphi29. The apparent similarities in the putative mechanisms...... of DNA replication and packaging of ABV to those of bacterial and eukaryal viruses are most consistent with the concept of a primordial gene pool as a source of viral genes....

  8. A loss of function analysis of host factors influencing Vaccinia virus replication by RNA interference.

    Directory of Open Access Journals (Sweden)

    Philippa M Beard

    Full Text Available Vaccinia virus (VACV is a large, cytoplasmic, double-stranded DNA virus that requires complex interactions with host proteins in order to replicate. To explore these interactions a functional high throughput small interfering RNA (siRNA screen targeting 6719 druggable cellular genes was undertaken to identify host factors (HF influencing the replication and spread of an eGFP-tagged VACV. The experimental design incorporated a low multiplicity of infection, thereby enhancing detection of cellular proteins involved in cell-to-cell spread of VACV. The screen revealed 153 pro- and 149 anti-viral HFs that strongly influenced VACV replication. These HFs were investigated further by comparisons with transcriptional profiling data sets and HFs identified in RNAi screens of other viruses. In addition, functional and pathway analysis of the entire screen was carried out to highlight cellular mechanisms involved in VACV replication. This revealed, as anticipated, that many pro-viral HFs are involved in translation of mRNA and, unexpectedly, suggested that a range of proteins involved in cellular transcriptional processes and several DNA repair pathways possess anti-viral activity. Multiple components of the AMPK complex were found to act as pro-viral HFs, while several septins, a group of highly conserved GTP binding proteins with a role in sequestering intracellular bacteria, were identified as strong anti-viral VACV HFs. This screen has identified novel and previously unexplored roles for cellular factors in poxvirus replication. This advancement in our understanding of the VACV life cycle provides a reliable knowledge base for the improvement of poxvirus-based vaccine vectors and development of anti-viral theraputics.

  9. The Host E3-Ubiquitin Ligase TRIM6 Ubiquitinates the Ebola Virus VP35 Protein and Promotes Virus Replication.

    Science.gov (United States)

    Bharaj, Preeti; Atkins, Colm; Luthra, Priya; Giraldo, Maria Isabel; Dawes, Brian E; Miorin, Lisa; Johnson, Jeffrey R; Krogan, Nevan J; Basler, Christopher F; Freiberg, Alexander N; Rajsbaum, Ricardo

    2017-09-15

    Ebola virus (EBOV), a member of the Filoviridae family, is a highly pathogenic virus that causes severe hemorrhagic fever in humans and is responsible for epidemics throughout sub-Saharan, central, and West Africa. The EBOV genome encodes VP35, an important viral protein involved in virus replication by acting as an essential cofactor of the viral polymerase as well as a potent antagonist of the host antiviral type I interferon (IFN-I) system. By using mass spectrometry analysis and coimmunoprecipitation assays, we show here that VP35 is ubiquitinated on lysine 309 (K309), a residue located on its IFN antagonist domain. We also found that VP35 interacts with TRIM6, a member of the E3-ubiquitin ligase tripartite motif (TRIM) family. We recently reported that TRIM6 promotes the synthesis of unanchored K48-linked polyubiquitin chains, which are not covalently attached to any protein, to induce efficient antiviral IFN-I-mediated responses. Consistent with this notion, VP35 also associated noncovalently with polyubiquitin chains and inhibited TRIM6-mediated IFN-I induction. Intriguingly, we also found that TRIM6 enhances EBOV polymerase activity in a minigenome assay and TRIM6 knockout cells have reduced replication of infectious EBOV, suggesting that VP35 hijacks TRIM6 to promote EBOV replication through ubiquitination. Our work provides evidence that TRIM6 is an important host cellular factor that promotes EBOV replication, and future studies will focus on whether TRIM6 could be targeted for therapeutic intervention against EBOV infection. IMPORTANCE EBOV belongs to a family of highly pathogenic viruses that cause severe hemorrhagic fever in humans and other mammals with high mortality rates (40 to 90%). Because of its high pathogenicity and lack of licensed antivirals and vaccines, EBOV is listed as a